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Combination Scanner May Increase Accuracy In Detecting Spread, Recurrence Of Head, Neck Cancer-(Science Daily 02/08/2005)A highly powerful scanner combining two state-of-the-art technologies -- computed tomography (CT) and positron emission tomography (PET) -- may detect the spread of head and neck cancer more accurately than other widely used imaging examinations. These findings, based on new research from the University of North Carolina at Chapel Hill School of Medicine, appear in the July issue of the medical journal The Laryngoscope. The whole-body PET/CT also is highly accurate for detecting head and neck cancer recurrence, the researchers said. "PET/CT is very helpful in determining where we should pinpoint our biopsies for recurrent disease," said Dr. Carol Shores, assistant professor of otolaryngology/head and neck surgery at UNC and the report's senior author. Shores is a member of the UNC Lineberger Comprehensive Cancer Center. "We can pick up cancer where we thought none existed. The new scans are so precise that in some cases cancer had been detected that probably would not have been through any other noninvasive imaging exam." Since its development in 2000, PET/CT imaging has enabled collection of both anatomical and biological information during a single examination. The PET component picks up the metabolic signal of actively growing cancer cells in the body, and the CT provides a detailed picture of the internal anatomy that reveals the size and shape of abnormal cancerous growths. "Alone, each test has its limitations, but when the results of the scans are integrated they provide the most complete information on cancer location and metabolism," said Shores. In cancer detection, the PET/CT has helped detect a variety of tumors, including cancers of the breast, esophagus, cervix, lung, colon and ovaries, as well as melanoma and lymphoma. "Until now, no published study has specifically evaluated clinical outcomes with PET/CT for head and neck tumors, including its accuracy, use and implications for patient care," said Shores. "In our review of nearly 100 patients at UNC, we wanted to find out where our best accuracy is in detecting these tumors with PET/CT." In PET/CT scanning, the patient lies on a table and is moved through the machine's doughnut-shaped tunnel twice, first to obtain the PET data and again for the CT. Cancer cells require a great deal of sugar, or glucose, to have enough energy to grow. PET scanning uses a radioactive molecule similar to glucose called fluorodeoxyglucose (FDG), which accumulates within malignant cells because of their high rate of glucose metabolism. The patient receives an injection of this agent, and the whole-body scanner detects evidence of cancer that may have been overlooked or difficult to characterize by conventional CT, PET, X-ray or MRI. In the new study, the PET/CT was shown to be 80 percent accurate for staging of distant metastasis, such as the spread of head and neck cancer to the lungs. This could affect the "intent of treatment," including decisions to preserve quality of life, Shores said. Lung metastasis of head and neck cancer is not curable, Shores added. In these cases, patients receive palliative care rather than aggressive therapy, including major surgery or combined chemotherapy and radiation treatment. Such intensive treatments may cause difficulties swallowing and speaking, severe pain and other problems. In addition to detecting distant metastasis, the study found the PET/CT more than 70 percent accurate in evaluating cancer recurrence. Future PET/CT studies at UNC will hone accuracy, Shores said. "We'll get more usable correct information because we now have a good idea of where we are most accurate." [Top]Compound From Chinese Medicine Shows Promise In Head And Neck Cancer-(Science Daily-17/07/2005)A compound derived from cottonseed could help improve the effectiveness of chemotherapy at treating head and neck cancer, researchers at the University of Michigan Comprehensive Cancer Center have found. The findings, which appear in the July issue of the journal Molecular Cancer Therapeutics, could lead to a treatment that provides an effective option to surgically removing the cancer, helping patients preserve vital organs involved in speech and swallowing. While new treatments in head and neck cancer have allowed some patients to undergo chemotherapy and radiation therapy instead of surgery, this form of cancer is often resistant to chemotherapy. When the cancer does not respond to these powerful drugs, patients must resort to surgery. "Patients really benefit long-term by avoiding surgery because the side effects of surgery for head and neck cancer can be particularly difficult for patients. It affects how you talk, how you swallow and how you breathe," says study author Carol Bradford, M.D., professor of otolaryngology at the U-M Medical School and co-director of the Head and Neck Oncology Program at the U-M Comprehensive Cancer Center. The compound, (-)-gossypol, works to regulate a protein called Bcl-xL that's overexpressed in cancer cells and makes these cells survive when they shouldn't. Shaomeng Wang, Ph.D., co-director of the Molecular Therapeutics Program at the U-M Comprehensive Cancer Center, discovered (-)-gossypol, a compound derived from a component of Chinese medicine. Gossypol comes from cottonseed and was once used in China as a male contraceptive. More recently, it's been tested as a cancer treatment. Wang found the negative isomer of gossypol binds at a site to block the active Bcl-xL protein. A prior study conducted by researchers in the U-M Head and Neck Oncology Program showed Bcl-xL protein is often highly expressed in head and neck cancers. In this study, researchers developed head and neck cancer cell cultures resistant to the chemotherapy drug cisplatin, a platinum-based drug frequently used to treat this type of cancer. They found cisplatin killed cells with a mutant form of the protein p53, but cells with normal p53 and high levels of Bcl-xL were resistant. The researchers then treated these cisplatin-resistant cell lines with (-)-gossypol and found that (-)-gossypol induced the drug resistant tumor cells to undergo programmed cell death. "These cisplatin resistant cells are exquisitely sensitive to (-)-gossypol. We can induce cell death in 70 percent to 90 percent of cells. This is a very impressive induction of cell death. It's because we are targeting the pathways these cells need to survive," says study author Thomas Carey, Ph.D., co-director of the Head and Neck Oncology Program at the U-M Comprehensive Cancer Center and a professor in the U-M School of Dentistry and the U-M Medical School. To test the principle that Bcl-xL and non-mutant p53 determine resistance to cisplatin in head and neck cancer cells, lead study author Joshua Bauer, a U-M graduate student in pharmacology, overexpressed Bcl-xL in tumor cells with mutant or non-mutant p53. Only cells with non-mutant p53 and high Bcl-xL became resistant to cisplatin. Bauer then treated these cells with (-)-gossypol and induced cell death. To further confirm the importance of Bcl-xL in cisplatin resistance, the researchers used a technique called inhibitory RNA to shut off expression of Bcl-xL in the drug-resistant cells. These cells became sensitive to cisplatin when Bcl-xL was turned off, confirming its role in drug resistance. "We believe novel agents that target Bcl-xL can improve survival for our patients," Carey says. In a previous study published in November 2004 in Clinical Cancer Research, Bradford, Carey and their team treated cell cultures of head and neck squamous cell carcinoma with the (-)-gossypol compound and found it inhibited tumor cell growth. Additional testing in animals was also positive and showed (-)-gossypol did not harm surrounding healthy tissue. Researchers hope to begin a clinical trial in head and neck cancer patients within a year, testing whether (-)-gossypol can be used along with chemotherapy to create a better response and avoid surgery. More than 29,000 people will be diagnosed in 2005 with head and neck cancers, which include cancer of the tongue, mouth, throat and voice box. University of Michigan holds a patent on the negative isomer, (-)-gossypol, and has licensed the technology to Ascenta Therapeutics of San Diego, Calif., for commercial development. Wang is one of three U-M Medical School faculty members who founded the company and has significant financial interest Cancer Therapy Dropped In U.S. Is Revived in China-(The New York Times-25/02/2005) Chinese biotechnology companies have long copied American drugs for use in their home markets. But one Chinese imitator may now save a novel cancer treatment from oblivion after it was abandoned by its American developer. Shanghai Sunway Biotech, a biotechnology company in Shanghai, has licensed worldwide rights to the therapy from Onyx Pharmaceuticals, based in Emeryville, Calif., people at both companies said. The therapy uses a virus that has been genetically modified to attack cancer cells but avoid normal cells. The treatment, called Onyx-015, elicited great interest among cancer researchers a few years ago when it showed the ability to shrink tumors in midstage clinical trials. But there were challenges delivering the therapy to tumors because the immune system attacks the virus. Some scientists also considered the treatment a form of gene therapy, a technique that fell into disfavor after the death of a teenager in a gene therapy trial at the University of Pennsylvania. Onyx stopped work on the virus treatment in 2003 to devote its money to a more conventional cancer drug that is now in late stage trials with Bayer, the German pharmaceutical company. Onyx could not find a partner willing to pay for further development of the virus therapy. Unbeknownst to Onyx, however, Sunway researchers duplicated its approach after reading a paper published by Onyx scientists in 1996. Sunway has taken the treatment through clinical trials in China and thinks it is close to winning approval to sell it for head and neck cancer. The first and only approval of a gene therapy by any regulatory agency in the world happened in China in 2003. That therapy, developed by SiBiono GeneTech, based in Shenzhen, uses a virus to deliver to tumors a gene called p53 that helps kill cancerous cells. SiBiono's approach is very similar to one being tested in late stage clinical trials by Introgen, a company in Austin, Tex. Saliva Holds Clues to Oral Cancer-(HealthDay News-03/01/2005) A major advance in using saliva to detect oral cancer is outlined in a study funded by the U.S. National Institute of Dental and Craniofacial Research. Scientists found they were able to measure for elevated levels of four distinct cancer-associated molecules in saliva. Using this method, they had a 91 percent accuracy rate in distinguishing between healthy people and those diagnosed with oral squamous cell carcinoma. This is the first study to report that distinct patterns of cancer-linked messenger RNA can be measured in saliva and indicate the presence of a developing tumor. The findings appear in the current issue of Clinical Cancer Research. Messenger RNA provides a chemical record that a particular gene has been expressed. The researchers used saliva and blood samples from 32 people who'd been diagnosed with oral squamous cell carcinoma but hadn't yet received treatment. They plan a larger study to determine if they can use saliva samples to distinguish between various stages of oral cancer. Cincinnati study of Chernobyl residents uncovers new cause of thyroid cancer-(Yahoo News-03/01/2005)Cincinnati University scientists studying papillary thyroid cancer in Chernobyl residents following the 1986 nuclear plant accident have identified a novel genetic mutation event that occurs as a result of their exposure to high levels of radioiodide. Yuri E. Nukiforov led a team of researchers from both Cincinnati University and the University of Munich in identifying a novel oncogene (a mutated and/or overproduced version of a normal gene that alone or together with other changes can convert a cell into a tumor cell) in papillary thyroid carcinomas that developed in patients exposed to radiation at Chernobyl. Their results are published in the January 3 issue of the Journal of Clinical Investigation. Mutations of the genes BRAF, RET, or RAS are found in 70% of all cases of papillary thyroid tumors. In sporadic tumors (where patients have not been exposed to high levels of radiation), the most common genetic mutational event occurs within the BRAF gene. In contrast, mutations observed in radiation-induced tumors most commonly involve fusion of one end of the RET gene to the opposite end of various other genes to create a "chimeric oncogene." The two most common gene rearrangement types are called RET/PTC1 and RET/PTC3. Both types of mutations promote transformation of normal cells into malignant cells. In their current study, Nukiforov and colleagues identified a novel oncogene in Chernobyl residents with papillary thyroid cancer. This oncogene resulted from fusion of part of the AKAP9 gene with one end of the BRAF gene; both genes are present within chromosome 7. The intrachromosomal AKAP9-BRAF fusion event resulted in the loss of portions of the BRAF protein that normally inhibit the kinase activity of BRAF. BRAF is then able to transmit uncontrolled signals to normal cells that promote their division and transformation into malignant tumor cells. In an accompanying commentary, Alfredo Fusco and colleagues from Università degli Studi di Napoli "Federico II", in Naples, state that this study "provides further evidence supporting the concept that chromosomal inversions represent the most typical molecular lesion in tumors occurring in Belarus and the surrounding region after the Chernobyl accident….the peculiar susceptibility of thyroid follicular cells to chromosomal rearrangement is remarkable." This study represents a major breakthrough in our knowledge of the genetic events involved in papillary thyroid initiation. It demonstrates that while BRAF activation is a common feature of both sporadic and post-Chernobyl thyroid cancers, it is the genetic event underlying BRAF activation that can differentiate between the two types of tumors, with a higher proportion of point mutations occurring in sporadic thyroid cancers and intrachromosomal inversion responsible for a larger percentage of radiation-induced tumors. At this stage, the signaling pathway activated as a result of these mutational events (known as the MAPK pathway) is the most attractive target for new drugs that may intervene in the development of human papillary thyroid carcinomas. Gene cancer link in areca chewers-(BBC News-17/11/2004) Some people who chew areca nuts could be genetically more prone to mouth cancer, a study shows. Chewing the nut, also known as the betel, is popular in Asia and among UK Asians as it contains arecoline - a stimulant thought to improve memory. All areca-nut chewers have an increased chance of mouth cancer. But scientists at Taiwan's National Yang-Ming University found variations in the HO-1 gene can increase the risk of developing cancer two-fold.The team looked at variations of the HO-1 gene in 147 areca chewers with mouth cancer, 71 with oral submucous fibrosis, a scarring condition of the mouth, and 83 people without mouth cancer. They found a certain variation of the gene was much more common in men with mouth cancer, according to the findings in the British Journal of Cancer. The gene helps to protect cells from damage by harmful agents such as UV irradiation or hydrogen peroxide. But studies have also suggested that it may be involved in promoting tumour growth and maintaining cancer survival. More than 153,000 cases of mouth cancer are diagnosed in Asia each year while 4,300 cases are found in the UK. Lead researcher Dr Shu-Chun Lin said: "We know that chewing areca nuts increases a person's risk of mouth cancer. But not everyone who takes up the habit develops mouth cancer so there must be genetic factors involved. Particular variations of the gene have been associated with an increased risk of heart or lung disease. This is the first study to look at whether different forms of the gene affect mouth cancer risk." Areca nut chewing is particularly common in men, with as many as one in five chewing it in areas of Asia. Dr Lesley Walker, director of cancer information at Cancer Research UK, urged people to be wary of chewing areca nuts. "We know that areca chewers run the risk of getting mouth cancer. This report suggests that if people chew areca and also possess this particular gene variant - their risk of the disease is even higher. Most cases of cancer are caused by a combination of genetic and environmental factors. It's important to remember that habit and lifestyle can have a big effect on the risk of mouth cancer. The best way to prevent the areca-related mouth cancer is to avoid chewing the nut on its own or in combination with tobacco." Bhutan
leads way with tobacco sales ban-(Yahoo News-18/11/2004) Bhutan will next month become the first country to ban tobacco sales outright. The small Himalayan Buddhist kingdom's trade ministry has given shops, hotels, restaurants and bars until Dec 17 - national day - to dispose of tobacco stocks or risk losing their trading licence. Illegal dealers will face a fine of about £113 - almost double average monthly pay. People will be allowed to bring cigarettes into Bhutan for personal use, but must pay 100 per cent duty. "We want no pollution and good health for our citizens," said a government official. But a poll for the Kuensel newspaper showed that half of those surveyed opposed the ban. New jawbone is grown for cancer patient-(Associated Press-10/08/2004) A German who had his lower jaw cut out because of cancer has enjoyed his first solid meal in nine years — a bratwurst sandwich — after surgeons grew a new jaw bone in his back muscle and transplanted it to his mouth in what experts call an "ambitious" experiment. According to this week's issue of the Lancet medical journal, the German doctors used a mesh cage, a growth chemical and the patient's own bone marrow, containing stem cells, to create a new jaw bone that fit exactly into the gap left by the cancer surgery. Tests have not been done yet to verify whether the bone was created by the blank-slate stem cells, and it is too early to tell whether the jaw will function normally in the long term, but the operation is the first published report of a whole bone being engineered and incubated inside a patient's body and transplanted. Stem cells are the master cells of the body that go on to become every tissue in the body. They are a popular area of research, with scientists trying to find ways to prompt them to make desired tissues and perhaps organs. While researchers debate whether the technique resulted in a scientific advance involving stem cells, the operation has achieved its purpose and changed a life, said Stan Gronthos, a stem cell expert at the Institute of Medical and Veterinary Science in Adelaide, Australia. "A patient who had previously lost his mandible [lower jaw] through the result of a destructive tumor can now sit down and chew his first solid meals in nine years ... resulting in an improved quality of life," said Mr. Gronthos, who was not connected with the experiment. The operation was done by Dr. Patrick Warnke, a reconstructive facial surgeon at the University of Kiel in Germany. The patient, a 56-year-old man, had his lower jaw and half his tongue cut out almost a decade ago after getting mouth cancer. Since then, he had only been able to slurp soft food or soup from a spoon. In similar cases, doctors can sometimes replace a lost jawbone by cutting out a piece of bone from the lower leg or from the hip and chiseling it to fit into the mouth. This patient could not have that procedure because he was taking a potent blood thinner for another condition and doctors considered it too dangerous to harvest bone from elsewhere in his body. Dr. Warnke and his group began
by creating a virtual jaw on a computer, after making a three-dimensional
scan of the patient's mouth. The information was used to create a thin
titanium micromesh cage. Several cow-derived pure bone mineral blocks the
size of sugar lumps were then put inside the structure, along with a human
growth factor that builds bone and a large squirt of blood extracted from
the man's bone marrow, which contains stem cells. The surgeons then
implanted the mesh cage and its contents into the muscle below the
patient's right shoulder blade. He was given no drugs, other than routine
antibiotics to prevent infection from the surgery. The implant was left in
for seven weeks, when scans showed new bone formation. It was removed
about eight weeks ago, along with some surrounding muscle and blood
vessels, put in the man's mouth and connected to the blood vessels in his
neck. Scans showed new bone continued to form after the transplant. Possible Link Between Tooth Whiteners and Oral Cancer Found- (HealthDayNews-09/08/2004) New research appears to raise questions about a possible link between tooth whiteners and oral cancer. Researchers at Georgetown University conducted two case studies and a retrospective study of fewer than 20 people with oral cancer and concluded that people who use tooth whiteners were more likely to get metastatic lymph nodes. The results did not establish any conclusive link between tooth whiteners and oral cancer but did raise some intriguing possibilities, according to the researchers. They noted that while carbamide peroxide and hydrogen peroxide generated in the tooth whitening process are not proven carcinogens, they cause local inflammation and mucosal trauma at high concentrations. The complex interactions of this inflammatory response, combined with other factors, have an unpredictable effect on tissues, according to the researchers. The research is to be presented at the International Conference on Head and Neck Cancer, which runs from Aug. 7 to 11 in Washington, D.C. Seattle study of Chernobyl finds thyroid cancer link-(The Seattle Post Intelligencer-08/08/2004) Seattle scientists studying cancer rates among the victims of the 1986 Chernobyl nuclear plant explosion have found the first direct link between thyroid cancer risk and individual radiation exposures. Dr. Scott Davis, an epidemiologist at the Fred Hutchinson Cancer Research Center, led a team of researchers in performing an analysis of thyroid cancer rates among Ukrainians who lived and worked near the site of the world's worst nuclear accident. The report is published in the September issue of Radiation Research. "Before Chernobyl, we almost never saw thyroid cancer in children," Davis said. The Chernobyl explosion killed 30 people immediately and exposed millions to radiation. Though it was known that cancer rates were higher in the region after the accident, there were no studies showing a direct correlation between the amount of radiation exposure and an individual's risk of cancer. Davis and his colleagues focused their attention on one isotope, iodine-131, because it can be tracked most easily because of the specific kind of cancer it causes and also because of the group's familiarity studying it at the Hanford Nuclear Reservation. "The doses were considerably higher at Chernobyl," said Davis. He and his colleagues led the Hanford Thyroid Disease Study, which found no clear evidence of higher rates of thyroid disease or cancer among those exposed to the Hanford site's airborne emissions. The Chernobyl study wasn't launched immediately after the accident largely because of Cold War barriers. But in 1990, a Russian helicopter pilot who had worked on the disaster and later developed leukemia came to Fred Hutchinson for a bone marrow transplant. Davis and his colleague, statistician Ken Kopecky, built on this clinical relationship to establish a scientific collaboration with the Russians to look into thyroid cancer rates. In 1992, after the Soviet Union collapsed, the study was launched. Working with local physicians,
the Seattle scientists identified 26 people under 20 years old who had
thyroid cancer. Comparing them with 52 healthy people who lived in the
same region, the Hutch team collected extensive information about diet,
lifestyle and other factors to estimate their likely exposure to I-131.
Iodine-131 is one of the primary radioactive isotopes emitted as airborne
waste from nuclear plants, and it tends to concentrate in milk or certain
other foods. After reconstructing exposures, Davis and his team found that
the incidence of thyroid cancer was 45 times greater among those who had
received the highest dose of I-131. "This is the first direct
demonstration of a dose-response relationship," Davis said. Laryngeal cancer patients studied-(Yahoo News-08/08/2004) Voice-related quality of life is better in laryngeal cancer patients following chemo-radiation compared to those who have a laryngectomy. Although the toxic effects of chemo-radiation adversely impact vocal function and these patients have worse quality-of-life scores than normal patients, the results are higher than those who have their larynx removed, according to U.S. researchers who compared the effects of the two treatments. "The key thing is that voice is better," said Dr. Kevin Fung, who conducted the research while at the University of Michigan, but is now an assistant professor in the department of otolaryngology at the University of Western Ontario in London, Ont. He and his Michigan colleagues gave 97 patients with advanced laryngeal cancer a single course of induction chemotherapy followed by assessment of response. Patients with a response of less than 50% underwent early salvage laryngectomy, and patients with a greater than 50% response underwent concurrent chemo-radiation followed by two cycles of adjuvant chemotherapy. To determine final tumour response, direct laryngoscopy and biopsy were performed eight weeks after radiation treatment, and all patients with persistent or recurrent disease received late salvage laryngectomy. The study's primary outcome measures were voice and swallowing function using the Voice-Related Quality Of Life (V-RQOL) measure and the Performance Status Scale for Head and Neck Cancer Patients (PSS-HN), and the way they took nutrition (i.e., nothing by mouth; tube feeds with trial oral intake; combined oral and tube feeds; nutritional supplements only taken by mouth; oral intake with nutritional supplements; and, oral intake alone with no supplements). The V-RQOL is a 10-item self-administered validated voice outcome measure. Scores are reported in two domains (social-emotional and physical functioning), and a total score, both ranging from 0 to 100, with a higher score indicating better voice-related quality of life. The PSS-HN is a three-item, observer-rated validated speech and swallowing outcome measure. The three items include eating in public, normalcy of diet and understandability of speech. Complete V-RQOL survey data were available for 56 patients who were alive and free of disease at the time of the survey, with a minimum followup of eight months, and completed PSS-HN data were available for 41 of them. Partial (greater than 50%) response after induction chemotherapy was achieved in 44 (78.6%) of patients, and the larynx was preserved in 37 (66.1%) patients. Salvage laryngectomy was performed in 19 (33.9%) of patients, of whom 12 were early salvage (after induction chemotherapy) and seven were late. The overall three-year survival rate was 86%. The 37 patients with an intact larynx demonstrated significantly higher mean V-RQOL scores (80.3) than the 19 laryngectomy patients (65.4), a finding that was consistent in the social-emotional and physical functioning domains. But no differences in V-RQOL score were found between early and late salvage laryngectomy, which surprised the researchers. They expected the benefits of early salvage laryngectomy following induction chemotherapy would include improved wound healing and better vocal function due to better vascularity and less soft tissue fibrosis, Dr. Fung said. Predictors of higher total V-RQOL scores were lower cancer stage, organ preservation and length of time since treatment. PSS-HN scores showed that understandability of speech was significantly better in patients with an intact larynx, but there was no difference in scores for eating in public and oral nutrition. The overall swallowing function was comparable between the two groups. However, patients with an intact larynx were more likely to obtain nutrition with oral intake alone without supplements compared to laryngectomees (88.9% vs. 64.3%, respectively). Based on all the findings, Dr. Fung said a multi-institution, randomized controlled trial of the induction regimen used in this study is now in preliminary stages. Longer followup of larynx preservation in a larger cohort of patients is needed to evaluate late toxicity and organ function since fibrosis after aggressive radiation regimes increases over time. Moreover, such measures of function and quality of life are important endpoints to help judge overall effectiveness as newer, more aggressive treatment protocols with toxicities are developed and evaluated, he said. Therapy Eases Thyroid Cancer's Side Effects-(HealthDayNews-17/06/2004) A new treatment reduces the unpleasant and often debilitating side effects of preparing thyroid cancer patients for treatment after they have surgery, says a new study. An international team of researchers, led by Johns Hopkins Medical Institutions and the University of Pisa in Italy, used a genetically engineered thyroid stimulating hormone (TSH) called thyrotropin alfa (rTSH) to destroy the small amount of thyroid gland tissue that often remains after thyroid cancer surgery. They were able to do this without having to withhold thyroid hormone medication. This meant that patients did not have to endure the temporary but unpleasant symptoms caused by thyroid hormone deficiency. These symptoms can include fatigue, weight gain, chilliness, depression, muscle cramps, and slowed thinking.The research will be presented in New Orleans at the annual meeting of the Endocrine Society, June 16-18. The study was funded by Genzyme Corp., which makes thyrotropin alfa. "Recovery from thyroid cancer has been very difficult for patients because thyroid medication -- to replace the thyroid hormone naturally produced by a healthy thyroid gland -- has traditionally been withheld for four to six weeks after surgery so radioiodine could be used to identify and destroy glandular tissue that remained," study co-lead investigator Dr. Paul Ladenson, chief of endocrinology at Hopkins, said in a prepared statement. WHO research body says formaldehyde is cancer-causing agent-(ET-16/06/2004) The International Agency for Research on Cancer ruled that the common chemical formaldehyde, to which more than one million workers are exposed in Europe, was a carcinogen. The IARC, part of the World Health Organisation, said there was sufficient evidence to show that formaldehyde caused cancer of the nose and mouth, which is relatively rare in developed countries. It said there was also strong but not sufficient evidence that leukaemia could be caused by formaldehyde, which is used in the production of resins used as adhesives and binders in the timber and paper industries. Formaldehyde is also used in the production of plastics and coatings, in textile finishing, in the manufacture of industrial chemicals and as a disinfectant and preservative. The IARC said the introduction of resins that released less formaldehyde and improved ventilation had decreased the level of exposure in recent years. Study finds no association between marijuana use and incidence of oral cancer-(Yahoo News-01/06/2004) Contrary to previous research findings that have suggested a link, marijuana use does not appear to be associated with an increased risk of developing oral cancer, according to a large, population-based study led by researchers at Fred Hutchinson Cancer Research Center. Their findings, the result of the most comprehensive evaluation to date regarding the association between marijuana use and the incidence of oral squamous-cell carcinoma, appear in the June issue of Cancer Research, a publication of the American Association for Cancer Research. The study, conducted in collaboration with researchers at the University of Illinois Urbana-Champaign and Seattle's Center for Health Studies, Group Health Cooperative, found no association between marijuana use and increased oral-cancer risk, regardless of how long, how much or how often a person has used marijuana. The study also found no increased risk among marijuana users who had other underlying risk factors for oral cancer, such as a history of tobacco use or heavy alcohol use.''When asking whether any marijuana use puts you at increased risk of oral cancer, our study is pretty solid in saying there's nothing going on there,'' said Stephen M. Schwartz, Ph.D., a member of Fred Hutchinson's Public Health Sciences Division and the senior author of the study. The study also found that marijuana smokers with certain common genetic variations that are known to interfere with the body's detoxification process are at no greater risk of oral cancer than those who carry normal copies of such genes. Specifically, the researchers found that marijuana users with defective versions of GST (gluthathione S-transferase) genes, a class of genes that produce detoxifying enzymes that help whisk toxic byproducts from the body, were at no greater risk of oral cancer than those who carry normal versions of GST. ''Our study isn't the last word on whether there are certain genetic factors that may put people who smoke marijuana at an increased risk of oral cancer, but at least with respect to GST, we didn't find any evidence that marijuana use caused a higher risk than expected in any genetic subgroups,'' said first author Karin A. Rosenblatt, Ph.D., an associate professor of community health in the College of Applied Life Studies at the University of Illinois at Urbana Champaign. The study involved 407 oral-cancer cases and 615 healthy control subjects from western Washington who had been interviewed in detail about their history of marijuana use, among other lifestyle factors. Participants, both male and female, ranged in age from 18 to 65. The oral-cancer cases were identified through a population-based cancer registry housed at Fred Hutchinson that is part of the National Cancer Institute's Surveillance, Epidemiology and End Results program. The National Cancer Institute and the National Institute of Dental and Craniofacial Research (both branches of the National Institutes of Health) funded the research. The Fred Hutchinson study counters findings from a smaller investigation, widely publicized in 1999, which suggested that ever-users of marijuana were at more than twice the risk of getting head-and-neck squamous-cell carcinoma as compared to non-users.''Our study casts a fair bit of doubt on the overall conclusion of the previous study,'' Schwartz said. The earlier study had a number of limitations, most importantly the fact that its control, or comparison, group was comprised of individuals who had donated blood at the same hospital where the oral-cancer cases had been treated. ''Blood donors tend to have fewer high-risk habits than the general population,'' Schwartz said, referring to the fact that they're screened for certain lifestyle factors such as intravenous-drug use as well as for previous infection with HIV and hepatitis. Blood donors might therefore be less likely to have a history of marijuana use, he said. ''We felt our study, which used controls selected from the general population, could more accurately determine whether oral-cancer patients were more likely to have used marijuana,'' he said. Another strength of the Fred Hutchinson study is that it involved nearly three times as many participants as the previous investigation, which included 173 oral-cancer cases and 176 healthy controls. ''The size of our study tends to make our findings statistically stable,'' Schwartz said. In addition, the Fred Hutchinson study collected much more detailed information about the participants' history of marijuana use than did the previous investigation, and it also included a greater proportion of long-term marijuana users; 10.9 percent of participants in the Fred Hutchinson study reported smoking marijuana for five or more years as compared to 3.5 percent of participants in the previous study. Despite the strengths of the most recent study, Schwartz is quick to point out its limitations. First, like the previous study, it relied on participants' self-reporting of marijuana use, which could have been somewhat biased. Second, only 60 percent if the intended subjects actually participated. ''However, those who did participate in the study appeared to be representative of what we'd expect in terms of lifestyle factors associated with oral-cancer epidemiology,'' Schwartz said. ''The oral-cancer patients in our study tended to smoke a lot more, they drank a lot more and they were of lower income and education level than the general population. In addition, our study's control group echoed national estimates of marijuana use.'' The study found similar marijuana-use patterns among oral-cancer cases and healthy controls. The majority used marijuana less than once a week, only 1 to 2 percent of cases and controls reported smoking marijuana daily or more, and only 6 percent of cases and 4 percent of controls reported having smoked marijuana for 15 years or more. Because the incidence of extensive, long-term marijuana use was so low among the study population - a reflection of the population at large - it is unclear whether extremely heavy use over many years is related to the risk oral cancer, Schwartz said. ''Certainly even for moderate levels of use our study is pretty solid in saying there's no association, but when you get out to heavy-use patterns we can't be sure, because the numbers are still too small,'' said Schwartz, also a professor of epidemiology at the University of Washington School of Public Health and Community Medicine. National surveys have found that about a quarter of the population has smoked marijuana at some point in their lives, and that about 4 percent of the population, or 6 million people, report occasional use of marijuana. While the incidence of casual marijuana use has remained stable during the past decade, habitual use/abuse appears to be on the rise. Two recent, nationally representative surveys by the National Institute on Drug Abuse found habitual marijuana use/dependence has increased more than 20 percent in the past decade among American adults, particularly young minorities and baby boomers. Such use is defined as repeated use of the drug that causes problems functioning at work, in school or in social situations, or creating marijuana-related legal problems. According to the American Cancer Society, more than 28,000 new cases of oral cavity/pharynx cancer are expected this year; incidence rates are more than twice as high in men as in women. The five-year survival rate for all stages combined is 57 percent. Routine Thyroid Cancer Procedure May Shortened-(Reuters Health-09/04/2004) A standard post-surgery routine that can leave thyroid cancer patients feeling run-down for weeks may be largely unnecessary, new research suggests The procedure, widely used for decades, calls for patients who have had their cancerous thyroid glands removed to go off of their normal hormone replacement therapy for six to eight weeks so that they can receive follow-up care. But in the new study, researchers found that just two weeks off of thyroid replacement was sufficient for about 90 percent of the 284 patients they assessed. This shortened time frame could cut the amount of time that patients suffer the side effects of stopping their normal hormone replacement therapy, according to the study authors. The thyroid is a gland in the neck that secretes hormones that help regulate metabolism. When thyroid hormone levels drop too low, a condition called hypothyroidism, metabolism slows, and symptoms such as fatigue, poor memory, weight gain and depression set in. So when the gland is removed due to cancer, patients must take synthetic replacement hormones for life. However, doctors have to temporarily stop patients' replacement therapy to give them radioactive iodine. Because the thyroid gland absorbs nearly all of the iodine that enters the body, radioactive iodine can be used to destroy cancerous thyroid cells. Alternatively, iodine can be given in a small amount to reveal on X-rays any residual cancer remaining after surgery. When patients stop their hormone replacement, the brain produces more thyroid-stimulating hormone (TSH), which causes any remaining thyroid cells in the body to become "really hungry for iodine," Dr. Perry W. Grigsby, the study's lead author, explained. So once TSH levels are high enough, any thyroid cells remaining after cancer patients' surgery will soak up the radioactive iodine. Doctors have traditionally thought that to get this TSH elevation, patients have to reduce thyroid medication levels for four to six weeks, then go off hormone replacement completely for two weeks. The problem is that this sends them into weeks of what Grigsby called "profound" hypothyroidism. "They feel really lousy," he told Reuters Health. "They're tired, worn out." To minimize the time that patients go through this misery, Grigsby and his colleagues at Washington University School of Medicine in St. Louis have relied on simply stopping patients' thyroid hormone therapy for two weeks. Their study, reported in the Journal of Nuclear Medicine, reviewed the records of 284 of these patients. It found that nearly 90 percent had sufficiently high TSH levels after about two weeks off of their medication. According to Grigsby, the standard, six- to eight-week routine arose from a recommendation made several decades ago that was essentially based on logic rather than scientific evidence. The rationale was that giving patients a weaker thyroid medication for several weeks would allow the body to clear the hormone--and boost TSH levels--more quickly once the medication was stopped. But the approach has not been backed up by evidence. "I think it's been basically a medical myth," Grigsby noted. In contrast, he said he thinks there is sufficient science to support his team's abbreviated tactic. Two other recent studies, he and his colleagues note, have also shown that at least 90 percent of patients reach the needed TSH level after two to three weeks off of hormone replacement. Oral cancer survey from Case dental school shows dental hygienist's role in catching cancer-(Yahoo News-19/04/2004) In one of the first national surveys of dental hygienists about their knowledge and screening practices for oral cancers, researchers at Case Western Reserve University's School of Dental Medicine found indications that while dental hygienists view screening for oral cancer an important component of their practice and possess comparable oral cancer knowledge with the general dentist in the private practice, they often do not carry out oral cancer screenings. According to the American Cancer Society, approximately 28,900 people were diagnosed in 2002 with oral cancers and 7,400 people would died as result of their disease. The overall five-year survival rate was 56 percent. Early oral cancer is often asymptomatic and if not caught during its earlier stages, the chances of surviving the disease diminish significantly, according to Dr. Danny R. Sawyer, professor and chairman of Case' department of oral diagnosis and radiology and assistant dean of didactic education. He conducted the study along with Dr. Marsha Pyle, Case associate dean for dental curriculum; Meredith Bailey, a second-year Case dental student; and Maureen Vendemia, professor of dental hygiene from Youngstown State University. The 25-question survey from Case was mailed to 2,000 randomly selected dental hygienists nationwide, with 575 individuals responding to questions about their oral cancer knowledge and oral cancer screening practices. The survey findings were presented at the 2004 annual research meeting of the American Dental Education Association and were compared to an oral cancer survey of dentists presented by the authors at the 2003 ADEA's annual meeting. Some of the findings
from the dental hygienist survey were: · Most dental hygienists place
a high level of importance on oral cancer screening, are trained to screen
for the cancers and ae non-smokers themselves. However, only 53 percent
do head and neck examinations on their patients. The Case surveys of dental hygienists and dentists coincide with American Dental Association efforts to raise awareness of oral cancer and increase cancer screenings by professionals in the dental field. Also the importance of the research findings will help Case rewrite the Case School of Dental Medicine's dental curriculum, which is currently under revision as the dental school strives to train the dentist for the 21st century. The research group encourages people to be proactive in their oral health care by suggesting that if an oral-cancer screening examination is not done with our routine dental care, then ask your dentist or dental hygienist to do one. "After all, early diagnosis offers the best chance for cure," stressed Sawyer. Routine Thyroid Cancer Procedure May Shortened-(Reuters Health-09/04/2004) A standard post-surgery routine that can leave thyroid cancer patients feeling run-down for weeks may be largely unnecessary, new research suggests The procedure, widely used for decades, calls for patients who have had their cancerous thyroid glands removed to go off of their normal hormone replacement therapy for six to eight weeks so that they can receive follow-up care. But in the new study, researchers found that just two weeks off of thyroid replacement was sufficient for about 90 percent of the 284 patients they assessed. This shortened time frame could cut the amount of time that patients suffer the side effects of stopping their normal hormone replacement therapy, according to the study authors. The thyroid is a gland in the neck that secretes hormones that help regulate metabolism. When thyroid hormone levels drop too low, a condition called hypothyroidism, metabolism slows, and symptoms such as fatigue, poor memory, weight gain and depression set in. So when the gland is removed due to cancer, patients must take synthetic replacement hormones for life. However, doctors have to temporarily stop patients' replacement therapy to give them radioactive iodine. Because the thyroid gland absorbs nearly all of the iodine that enters the body, radioactive iodine can be used to destroy cancerous thyroid cells. Alternatively, iodine can be given in a small amount to reveal on X-rays any residual cancer remaining after surgery. When patients stop their hormone replacement, the brain produces more thyroid-stimulating hormone (TSH), which causes any remaining thyroid cells in the body to become "really hungry for iodine," Dr. Perry W. Grigsby, the study's lead author, explained. So once TSH levels are high enough, any thyroid cells remaining after cancer patients' surgery will soak up the radioactive iodine. Doctors have traditionally thought that to get this TSH elevation, patients have to reduce thyroid medication levels for four to six weeks, then go off hormone replacement completely for two weeks. The problem is that this sends them into weeks of what Grigsby called "profound" hypothyroidism. "They feel really lousy," he told Reuters Health. "They're tired, worn out." To minimize the time that patients go through this misery, Grigsby and his colleagues at Washington University School of Medicine in St. Louis have relied on simply stopping patients' thyroid hormone therapy for two weeks. Their study, reported in the Journal of Nuclear Medicine, reviewed the records of 284 of these patients. It found that nearly 90 percent had sufficiently high TSH levels after about two weeks off of their medication. According to Grigsby, the standard, six- to eight-week routine arose from a recommendation made several decades ago that was essentially based on logic rather than scientific evidence. The rationale was that giving patients a weaker thyroid medication for several weeks would allow the body to clear the hormone--and boost TSH levels--more quickly once the medication was stopped. But the approach has not been backed up by evidence. "I think it's been basically a medical myth," Grigsby noted. In contrast, he said he thinks there is sufficient science to support his team's abbreviated tactic. Two other recent studies, he and his colleagues note, have also shown that at least 90 percent of patients reach the needed TSH level after two to three weeks off of hormone replacement. Local chapter of American Cancer Society urges checking-(Yahoo News-29/03/2004) February was "Oral Cancer Awareness" month, sponsored by Baldwin County's unit of the American Cancer Society, the largest private, not-for-profit source of cancer research funds in the United States. Second only to the federal government in total dollars allocated for cancer research, the American Cancer Society has continuously sponsored research projects to help identify and design more effective means of detection and treatment. The American Cancer Society states that many cancers of the oral cavity and oropharynx can be found early, during routine screening examinations by a doctor or dentist, or by self-examination. Some early cancers have symptoms that cause patients to seek medical or dental attention. Unfortunately, others may not cause symptoms until after reaching an advanced stage or may cause symptoms that appear to be due to a disease other than cancer, such as a toothache. Many physicians and dentists recommend that people take an active role in the early detection of oral and oropharyngeal cancers and precancerous conditions by doing self-examinations. The American Cancer Society recommends that primary care doctors examine the mouth and throat as part of a routine cancer-related checkup. This means looking in a mirror to check for any of the findings included in the following list: a sore in the mouth that does not heal (most common symptom); pain in the mouth that doesn't go away (also very common); a persistent lump or thickening in the cheek; a persistent white or red patch on the gums, tongue, tonsil, or lining of the mouth; a sore throat or a feeling that something is caught in the throat that doesn't go away; difficulty chewing or swallowing; difficulty moving the jaw or tongue; numbness of the tongue or other area of the mouth; swelling of the jaw that causes dentures to fit poorly or become uncomfortable; loosening of the teeth or pain around the teeth or jaw; voice changes; a lump or mass in the neck; and weight loss. Many of these signs and symptoms may be caused by other cancers or by less serious, benign problems. If you have any of these signs or the condition lasts more than two weeks, it is important to see a medical doctor or dentist as soon as possible. Oral Sex Shown to Be Linked to Mouth Cancer-(ET-25/02/2004) Although the risk is small and it is more likely to result from heavy drinking and smoking, scientists have uncovered evidence that oral sex can cause mouth cancer. Researchers had suspected that a sexually transmitted infection that is linked to cervical cancer could also be associated with tumors in the mouth. Now a study by researchers working for the International Agency for Research on Cancer (IARC) in Lyon, France seems to have confirmed it. "Oral sex can lead to oral tumors," New Scientist magazine said, referring to the latest research. The scientists studied more than 1,600 patients from Europe, Canada, Australia, Cuba and the Sudan with oral cancer and more than 1,700 healthy people. They found that patients with oral cancer containing a strain of the human papilloma virus (HPV) known as HPV16 were three times more likely to report having had oral sex than those without the virus strain. "The researchers think both cunnilingus and fellatio can infect people's mouths," the magazine added. Raphael Viscidi, a virologist who worked on the research, believes the findings substantiate the link between HPV and oral cancer. "This is a major study in terms of size," he said. "I think this will convince people." High consumptions of alcohol and cigarettes are estimated to cause 75-90 percent of all cases of oral cancer. The combination of tobacco smoke and alcohol are thought to produce high levels of cancer causing agents. Scientists are currently working on vaccines to prevent cervical cancer, which is more common, but they might also be effective against oral cancer. "It is thought the vaccines would prevent oral infections as well," the magazine added Anemia Drug May Weaken Radiation Treatments for Head and Neck Cancers-(ET-27/10/2003) A multi-center European study published in The Lancet (Vol. 362, No. 9392: 1255-1260) found that an experimental use of an anemia drug in some cancer patients going through radiation treatments may have worsened control of the cancer. Experts said the results are unlikely to change the current US practice of administering the drug, called erythropoietin or epoetin, to patients whose anemia is causing problems like fatigue. But the study raises some important questions about what many doctors consider a potentially promising new application for this widely used drug. Anemia drugs like epoetin increase levels of hemoglobin, the compound in red blood cells that carries oxygen to the tissues. Because radiation is more effective against cells with high oxygen concentrations, many researchers have theorized that giving patients these drugs would raise the oxygen level in tumors and help patients respond better to their treatment. In the new study, however, the opposite happened. "It's a very disappointing result," said Jerome Seidenfeld, PhD, associate director of the Technology Evaluation Center of the Blue Cross and Blue Shield Association, who helped compile guidelines for epoetin use published by the American Society of Clinical Oncology. Researchers led by Michael Henke, MD, of the University of Freiburg in Germany compared 351 head and neck cancer patients who began receiving either epoetin-beta or a placebo about two weeks before radiotherapy began, and continued the treatment throughout the course of radiation. The researchers found that patients on epoetin-beta fared worse in terms of tumor control and survival than those given a placebo, although their hemoglobin levels did increase. The study raises many important questions, experts said. Might the negative effect on tumor control also apply to patients with other kinds of cancer who are receiving anemia treatment with chemotherapy, too? Is the impairment of tumor control related to the drug itself, or to the increase of hemoglobin caused by the drug? More research is needed to make those determinations. "I think one should always interpret a single clinical trial in just that light: It's a single clinical trial," said Douglas Rizzo, MD, an associate professor of medicine at the Medical College of Wisconsin and another member of the ASCO epoetin committee. He noted that many of the patients in this trial did not complete it correctly -- their radiation treatments were not given properly, or they had medication errors. That could have affected the strength of the statistical analysis, he said. In addition, many patients in this trial had hemoglobin levels higher than what US doctors generally use as a guide to determine who should get epoetin. Rizzo suggested it was premature to generalize the results of this study to patients with other cancer types or those receiving chemotherapy. He noted that in an earlier study of cervical cancer patients receiving both chemotherapy and radiation, epoetin did appear to improve relapse-free survival. "I don't know that this should substantially change practice for patients with substantial fatigue and low hemoglobin," he said. Seidenfeld agreed. "What remains true is that ...treating (anemic patients) with erythropoietin is going to make them feel better and is going to reduce the likelihood that they'll need a transfusion down the line," he said. Frequent Radiation Better For Head, Neck Cancer-(HealthDayNews-18/09/2003) A Danish report of better results in treating head and neck cancer with accelerated doses of radiation isn't the breakthrough that many people might suppose -- and that is cheerful news. The reason: Treatment of this kind of cancer has advanced so rapidly since the Danes began the study that the results are already outmoded, experts say. Centers across the United States already are using combined therapy that gives much better results than those reported in the study. "This would have been big news in 1992," says Dr. Nancy Lee, an assistant attending physician in radiation oncology at Memorial Sloan-Kettering Cancer Center in New York City. "Radiation technology has changed dramatically over the last five years." The newer technology, not used in the Danish trial, allows precise targeting of radiation against a cancer, Lee says. And it now is combined with chemotherapy, which improves the results even more. The Danish trial did not use the combination treatment The Danish study, published in the Sept. 20 issue of The Lancet, found that giving a fixed dose of radiation faster, with six treatments a week rather than five, improved results considerably, with tumor control -- meaning the cancer was no longer evident -- achieved in 70 percent of patients, rather than the 60 percent control rate of the five-dose-a-week regimen. "It is an interesting observation, but let's not get excited," says Dr. Jatin P. Shah, chief of the Memorial Sloan-Kettering head and neck service. "The science has moved on much more than was done in this trial." Tumor control rates of 80 percent to 90 percent how are being achieved routinely, even in more advanced cases of head and neck cancer, Lee says. The Danish study included a large number of less advanced tumors, which are easier to control. There will be 55,000 new cases of head and neck cancer causing 13,000 deaths in the United States this year, the National Cancer Institute estimates. The leading cause is smoking. There are good things to say about the Danish study, says Dr. Eric M. Horwitz, a radiation oncologist at Fox Chase Cancer Center in Philadelphia. It is the kind of carefully controlled trial that is regarded as the gold standard in clinical research, he says, and the finding that giving radiation treatment faster is being applied to patients with less advanced stages of the disease. Head and neck cancers are classified in four stages, each number indicating a more advanced stage of the condition. Less advanced cases generally are treated with radiation alone. "If you can shorten the time in stage 1 and 2 patients, it does make a difference," Horwitz says. "But for stages 3 and 4, you don't use radiation alone. In all the big clinical trials stages 3 and 4 are treated with combined radiation and chemotherapy." Endostatin Effective Treatment for Head and Neck Cancers-(ET-14/08/2003) Researchers at Ohio State University found that endostatin has a dual effect on head and neck cancer cells -- the compound prevented the cells from developing new blood vessels and also hindered the mechanism cancer cells use to migrate throughout the body and invade other tissues. Head and neck cancers originate on the epithelium -- the layer of tissue covering the outermost surfaces of the body, including the skin and mucus membranes. Kaposi's sarcoma tumors arise from the endothelium, the cells that line blood vessels. "The vast majority of endostatin studies have concentrated on endostatin's effects against endothelial cells, and haven't focused on the drug's anti-tumorigenic possibilities," said Susan Mallery, the study's lead author and a professor in the Ohio State College of Dentistry's department of oral and maxillofacial surgery and pathology. "We wanted to explore other options for endostatin use," she said. After getting promising laboratory results with treating oral cavity tumor cells taken from men with oral cancer with endostatin, Mallery is suggesting the possibility of an implanted drug delivery system, one that could deliver endostatin directly to the site of a tumor after it was surgically removed. "About half of all people with head and neck cancers die as a result of local disease recurrence," Mallery said, adding that such cancers account for about 7 percent of all cancers in the United States. "Another major concern is patient compliance with follow-up treatment after the original tumor is removed. "It's possible that one day doctors could treat these patients with an implanted delivery device that dispenses a sustained, therapeutic drug concentration right where it is needed the most -- where the tumor was," she continued. "Such a treatment option not only provides a constant therapeutic drug level, it also eliminates concerns regarding patient compliance." In the current study, endostatin treatment reduced by half the number of invasive head and neck cancer cells, and also reduced the number of cells capable of migration by one-quarter. Migrating cells receive some sort of chemical signal before moving in a directed fashion throughout the body. Invasive cells migrate, but they also produce an enzyme that actually digests the membranes of the cells they're trying to take over. The research appears in a recent issue of the journal Anticancer Research. Mallery and her colleagues received funding from the National Institutes of Health/National Institute of Dental and Craniofacial Research and from the Ohio Division of the American Cancer Society. Triple Whammy Beats Childhood Cancer-(HealthDayNews-24/06/2003) A combination of three therapies seems to successfully treat retinoblastoma, a deadly childhood cancer that begins as a tumor in the eye. Treating patients with high-dose chemotherapy, radiation therapy and transplantation of blood-producing stem cells helps fight retinoblastomas that have spread to the bones, bone marrow and soft tissue, say researchers at St. Jude Children's Research Hospital in Memphis, Tenn. The team reports their finding in the June issue of Ophthalmology. Their study included four children with retinoblastoma. In all the children, the bone marrow disease went into remission after two courses of chemotherapy, which was followed by radiation and stem cell therapy. Two of the children survived free of disease for more than six years. In the other two children, the cancer recurred in the central nervous system and they didn't survive. "Our results show that retinal tumors that metastasize to other areas of the body can be cured. Chemotherapy by itself only results in transient improvement, with all patients dying of disease progression eventually, whereas chemotherapy in combination with radiation and stem cell therapies can actually save patients' lives," lead author Dr. Carlos Rodriguez-Galindo says in a news release. "We believe more than 90 percent of patients can be cured with surgery if the disease is detected early enough, before the disease spreads," he adds. Rodriguez-Galindo and other researchers are developing a national protocol that will apply these treatment principles to all children with retinoblastoma. It's estimated that between 300 and 350 children in the United States are diagnosed with retinoblastoma each year. Of those, about 5 percent develop retinal tumors that spread outside of the eye. Oxigene Thyroid Cancer Drug on Fast-Track-(Reuters-04/06/2003) Oxigene Inc.'s experimental thyroid cancer treatment will get an accelerated review by U.S. regulators, the company said. Its drug, called Combretastatin A4 Prodrug, is currently being evaluated in mid-stage, or Phase II, clinical trials. The drug received "fast-track" status from the U.S. Food and Drug Administration, meaning the agency will accept initial data from late-stage, or Phase III, trials instead of waiting for all trial data to be submitted together. The Oxigene treatment is a so-called anti-angiogenesis drug, designed to cut off the blood supply to tumors, essentially starving them to death. A recent four-day meeting of oncologists in Chicago produced encouraging research on several other experimental cancer drugs that pushed up biotechnology stocks like ImClone Systems Inc. and Genentech Inc. Anti-angiogenesis drugs fell out of favor over the past few years as clinical trials failed. But the class of drugs got a major boost when Genentech said last month its Avastin drug was effective in colon cancer patients. Fiber May Reduce Risk of Laryngeal Cancer-(Cancer.com-21/04/2003) According to an article recently published in the Annals of Oncology, people consuming fiber from vegetables and fruits, as opposed to fiber from grain sources, have significantly lower rates of laryngeal cancer. The larynx is a short passageway located below the pharynx in the neck. The larynx houses the vocal cords, which make sound when air passes through them. Approximately 10,000 Americans are diagnosed with laryngeal cancer every year. This cancer, classified as a type of head and neck cancer, may be treated with radiation therapy, chemotherapy, and/or surgery. Many surgeries for laryngeal cancer result in removal of the voice cords. One important goal of cancer research is to identify environmental risk factors for different types of cancer. Some factors such as diet, exercise, pollution, and stress have been associated with a higher incidence of specific cancers. Conversely, other factors have been associated with a lower incidence of certain cancers. Researchers continue to evaluate environmental factors that may either increase or decrease the risk of developing certain types of cancer so that better strategies for prevention and/or screening can be produced and implemented. Several clinical trials have reported that fruits, vegetables, and whole grains appear linked to lower levels of laryngeal cancer. However, which types of dietary fiber confer the most protection is unknown. Italian researchers conducted a study involving 527 laryngeal cancer patients and 1,297 cancer-free patients staying in the same hospital together. All patients answered food-frequency questionnaires, describing what types of food they ate and how often they ate them. Overall, patients with the lowest levels of fiber intake were 70% more likely to develop laryngeal cancer than patients with the highest fiber levels. Patients getting a large quantity of their fiber from vegetables were 80% less likely to have laryngeal cancer, while patients consuming large quantities of fruit were 50% less likely to develop laryngeal cancer. Fiber from grain sources did not confer any protection from laryngeal cancer. Researchers cannot explain how fiber lowers risk of laryngeal cancer. Nonetheless, they recommended eating more fruits and vegetables, and cutting back on refined breads, to reduce ones overall risk of developing cancer. Tracking Oral Cancer's Growth-(HealthScoutNews-17/03/2003) There are distinct stages in a cell's evolution from healthy to cancerous, and understanding the characteristics of each stage can improve diagnosis and treatment, says a Medical College of Georgia researcher. Dr. Baldev Singh is a professor of oral biology and maxillofacial pathology and an expert on oral cancer cells. Oral cancer is one of the few cancers with an unchanged death rate over the last 25 years. About 66 percent of blacks and 44 percent of whites die within five years of being diagnosed with oral cancer. Tobacco is the chief risk factor for oral cancer, characterized by white lesions in the mouth. Oral cancer, which is often diagnosed by dentists, is visible and observable as it progresses. Singh has studied oral cancer and precancerous cells microscopically. He's grown the cells in their sequential stages to develop a model that traces oral cancer progression. This model may help lead to earlier diagnosis of oral cancer, when treatment is more effective. Findings Tie Gum Disease to Mouth Cancer-(Reuters Health-20/03/2003) People with gum disease are twice as likely to have precancerous abnormalities in their mouths, and have a more than four-fold risk of mouth cancer, new study findings show. The study's lead author, Dr. Sara Grossi of the University of Buffalo in New York, said she believes these findings provide the first link between oral cancer and oral infection, and could offer a new strategy for identifying oral cancer in its early stages and perhaps preventing the disease. She reported the findings at the American Association of Dental Research's annual meeting. Gum disease, or periodontitis, is a chronic bacterial infection of the gums that can eventually lead to tooth loss. Some studies have linked gum disease to a higher risk of heart disease and stroke. Grossi and her colleagues analyzed data from the Third National Health and Nutrition Examination Survey (NHANES III), which the U.S. Centers for Disease Control and Prevention conducted between 1988 and 1994. Specifically, the team looked at roughly 14,000 study participants who were 20 or older and had six or more natural teeth. The researchers found that people with periodontal disease had a 1.74-fold increased risk of precancerous mouth lesions, and a 4.23 times greater risk of mouth cancer. "Survival from oral cancer, as with most cancers, depends on the stage of the disease at diagnosis," Grossi noted in a university statement. "If further studies demonstrate that periodontal disease is a significant risk and a warning sign, screening and oral examinations for oral cancer can be targeted in order to improve prevention and early detection of oral cancer." Aspirin May Cut Risk of Throat Cancer-(Reuters-04/03/2003) Taking low-dose aspirin regularly could cut the risk of developing cancers of the mouth, throat and esophagus, Italian researchers said. Millions of people already take the painkiller to relieve headaches and arthritis and to prevent heart attacks and stroke. Studies have also suggested the century-old drug could have a protective effect against bowel and lung cancer. Researchers at the Institute of Pharmacological Research in Milan have now shown that aspirin can slash the risk of mouth and throat cancer by two-thirds. "We found aspirin had a protective effect against cancer of the upper aerodigestive tract," Dr. Cristina Bosetti, an epidemiologist at the institute, said in an interview. Bosetti and her team analyzed three previous studies involving 965 cancer patients who had been taking aspirin for other problems, such as heart disease, for five years. The cancer patients and nearly 1,800 other people filled in questionnaires about their smoking and drinking habits, diet and how often they took aspirin. The research, which is reported in the British Journal of Cancer, revealed fewer mouth and throat cancers in the patients who had been taking aspirin for the five years or more. "This is the first study which reports such protection. Few studies have been conducted on aspirin and the upper aerodigestive tract," Bosetti added in a statement. The researchers believe aspirin may play a role in cutting cancer risk because of its impact on an enzyme called cyclooxegenase-2, which is involved in inflammation and is thought to be linked to the development of cancer. They also suspect aspirin may play an important role in preventing stomach, prostate and breast cancer. "The effect of aspirin can also be seen in other cancers because cyclooxegenase is also implicated in cancer of the stomach and breast cancer. If this is the mechanism of action the effect of aspirin could be similar for these cancers," Bosetti said. Dr. Richard Sullivan, of the charity Cancer Research UK, said the research is further proof that aspirin, which began as a simple painkiller, is one of the greatest finds in the history of drug discovery. "We're not yet at the stage where we can recommend that everyone starts taking aspirin on a daily basis, as we'll need to further investigate its effectiveness and possible side-effects of long-term use. However, it looks as though the drug could become an important part of cancer prevention," he added. Tongue Surgery May Help Patients with Mouth Cancer-(Reuters Health-01/01/2003) Surgeons at Washington University School of Medicine have developed a new surgical technique to help restore speech and tongue function in patients who've had surgery to remove cancer of the mouth. About 30,000 Americans develop mouth cancers each year. Most are caused by alcohol and tobacco use, and the tongue is the site most often affected. Surgeons must remove a portion or even all of the tongue to eradicate the cancerous tumors. It can be a very maiming operation, impairing a patient's ability to speak and swallow. "It's important to completely remove everything, we don't want to leave even one cancerous cell," said Dr. Bruce H. Haughey, associate professor of otolaryngology for the Washington University School of Medicine. "Then we do a commensurate reconstruction of what's left of the tongue." Earlier attempts to restore tongue function involved transferring a chest wall muscle to the floor of the mouth in an effort to replace the tongue. However, the transferred muscle was immobile and offered no sensation, Haughey said. In a new technique, Haughey and colleagues remove the cancer and create a replacement tongue in a 10-hour procedure that involves taking tissue from the forearm or thigh, where thickness is best and nerve tissue is available. The surgeons construct a new tongue by rolling and folding the tissue on top of itself to model the original. "It's almost an origami-like set of moves," said Haughey. Haughey and colleagues conducted a study of 43 men and women with an average age of 58. About half had their tongue removed due to cancer and had it reconstructed at the same time. The front portion of the tongue was reconstructed in 30 patients, and 13 had the base of the tongue reconstructed. The researchers report their findings in the Archives of Otolaryngology-Head and Neck Surgery. "These are an original set of techniques, nothing like this has been published before," said Haughey. Postoperative swallowing and airway results were assessed for 38 patients. Of those, 85% were able to swallow with mild to moderate difficulty, the others had to be fed through a tube. Only 30 patients were available for speech evaluation. A speech pathologist asked them to speak 50 words into a tape recorder to evaluate speech intelligibility. Then the tapes were played back to five people with no experience listening to head and neck cancer patients. Patients who had the base of their tongue reconstructed scored an overall intelligibility score of 98%. Those who received a new front portion of the tongue had an overall score of 76%. But the procedure is only effective for patients diagnosed with cancer of the mouth who have not had previous surgery to remove the tongue. "It's sad, because we'll get a call from someone who says my husband has had his tongue removed and he can't speak or swallow, and we have to tell her there's really nothing we can do," said Haughey. In an interview, Dr. Willard E. Fee, Jr., a professor of otolaryngology at Stanford University Medical Center, noted that it's important to consider the added expense and hospitalization time when deciding to undergo this type of reconstruction procedure. Fee has no affiliation with the Washington University study. He says there is still no satisfactory procedure for total or even partial tongue reconstruction. However, there is a good amount of research into cell cloning and organ regeneration that might change the field some day, he said. "Organ regeneration, that's where the real benefit is," said Fee, "I just hope I'm still alive for that." Chinese Fish Sauce May Up Esophageal Cancer Risk-(Reuters Health -13/06/2002) A fermented fish sauce commonly used as a relish in southern China and some other parts of Southeast Asia may account for the unusually high number of cases of esophageal cancer in the area, Chinese researchers report. In a study of more than 1,200 people with esophageal cancer and a matching group of cancer-free people from the same area in China, people who ate the fish sauce, known as yulu in China and harm ha in the Philippines, were more than three times as likely to have esophageal cancer. The more frequently people ate the sauce, the higher their risk of cancer, according to a report in a recent issue of the International Journal of Cancer. Compared to people who never ate the fish sauce, individuals who reported eating it every day were almost 16 times more likely to develop esophageal cancer. Smoking and drinking are well-established risk factors for esophageal cancer, but only smoking seemed to interact with consumption of fish sauce to increase cancer risk even further, the researchers report. As far as the researchers know, this is the first report of a link between fermented fish sauce and a high risk of esophageal cancer, Ke said. Ke's team decided to study the relationship between fermented fish sauce and esophageal cancer to see whether the food played a role in the high incidence of esophageal cancer in the Chaoshan area of Guangdong province in southern China. Yulu, the fish sauce, is very popular in this region, and previous research has suggested that fermented fish sauce may increase the risk of several types of cancers, including stomach cancer and thyroid cancer. Based on the results of the study, Ke recommends that people in this region make changes to their diet to reduce their risk of esophageal cancer. Exactly how the fish sauce may increase the risk of cancer is still uncertain, though. The condiment may contain substances that either cause cancer or promote its growth once it develops, the authors speculate. Noting that the risk of esophageal cancer was particularly high in people who ate fish sauce and smoked, the researchers suggest that substances in the sauce may enhance the effects of cancer-causing chemicals in cigarettes. Head and Neck Cancers Rising Among U.S. Kids-(Reuters Health-19/06/2002) Childhood cancer has been on the rise over the past couple of decades in the US and elsewhere, but cancers of the head and neck appear to be outpacing other cancers among American children, according to a new report. The reasons are unclear and may include factors ranging from better reporting of cases to environmental and prenatal causes, researchers say. Head and neck cancers usually strike older adults and include a range of malignancies, such as throat cancer and oral cancer. Overall, head and neck cancers are rare in children, and when they occur often come in the form of lymphoma in the lymph nodes of the neck or a handful of other diseases. In the current study, researchers analyzed the 3,050 pediatric head and neck cancers reported to the US national cancer registry between 1973 and 1996. They found that the incidence of these cancers among children younger than 15 rose 35% between 1973-1975 and 1994-1996--from 1.1 case per 100,000 children each year to just under 1.5 cases per 100,000. This increase compares with a 25% rise in cancer overall for this age group, according to findings published the June issue of the Archives of Otolaryngology Head & Neck Surgery. Dr. James T. Albright of Children's Hospital and Health Center in San Diego, California, led the study. Lymphoma involving the head and neck was the most common of these types of cancer, affecting 27% of the children in the national database. That was followed by cancers affecting nerve tissue--including retinoblastoma, an inherited cancer of the retina--and cancer of the thyroid gland. When Albright's team looked specifically at retinoblastoma, they found no increase in the disease over time. This, the authors write, suggests that non-genetic factors may be behind the two-decade rise in pediatric head and neck cancers. Well-established environmental factors implicated in pediatric head and neck cancers include ionizing radiation, excessive sun exposure and certain chemotherapy drugs, according to Albright and his colleagues. They note that environmental pollution, infection and parental exposure to toxins are suspected, but unproven, contributors. Premature birth and low birth weight have also been associated with a higher-than-average risk of childhood cancer, the report indicates. The researchers point out, though, that better reporting of childhood head and neck cancers over time might also have contributed to the increase they found. "Research on a variety of potential carcinogens is ongoing," Albright's team writes. "Continued surveillance is necessary." Combination Therapy Doesn't Help Head, Neck Cancers(HealthScoutNews-20/05/2002) Adding the powerful cancer drug cisplatin to radiation therapy doesn't seem to improve the outlook over radiation alone in people with head and neck tumors. That's the surprising and disappointing early return from an ongoing study comparing the two therapies. The research leaders stress the latest results are interim, and many patients hadn't reached the crucial two-year mark when the data was analyzed. However, the initial trends suggest the combination's benefits will be minimal at best. "People are always looking for things to do for patients," says Dr. Arlene Forastiere, of Johns Hopkins University's Kimmel Cancer Center and a co-chair of the study team. "We may be able to find a subset of patients that [the combination] helps, but right now, to our surprise, we're not seeing positive results." Head and neck tumors -- such as those of the voice box, throat and mouth -- strike nearly 29,000 Americans a year, killing 7,400, according to the American Cancer Society. The disease is particularly nasty, lethal within five years for more than half of people in whom it's diagnosed. The standard of care for these tumors has been to remove them surgically, and then use radiation to kill off residual cancer cells and prevent tumors from returning. For people who aren't good candidates for surgery, doctors use cisplatin -- a platinum-based compound prescribed for lung, breast, bladder and other cancers -- and radiation. Cisplatin plus radiation has also worked in patients with other forms of cancer, including tumors of the uterus and esophagus, says Dr. Jay S. Cooper, a radiation expert at New York University Medical Center and another co-chair of the study team. So, researchers wondered with good reason if adding cisplatin to radiation might improve the prognosis for head and neck tumor patients who qualify for surgery. The latest evidence, reported this weekend at a meeting of the American Society of Clinical Oncology in Orlando, Fla., suggests the answer to that question is a qualified no. Beginning in 1995, Forastiere, Cooper and their colleagues at clinics across the country have followed 407 people who had surgery to remove head and neck tumors. Of those, all received radiation and roughly half were given up to three doses of cisplatin to augment that treatment. After an average of 27 months of follow-up, outcomes in the two groups were similar. Tumors had returned in 26 percent of the patients who received radiation alone and in 20 percent of those in the other group -- but that difference wasn't statistically significant. Survival rates were also essentially identical, 63 percent in the combined treatment group versus 57 percent in the radiation group. Patients who took cisplatin were more likely to be cancer-free during the follow-up period -- 54.2 percent versus 42.5 percent. However, that gain came at a price: The drug is highly toxic, and only 58 percent of patients were able to tolerate all three doses. Serious side effects from the drug were more than twice as common as with radiation alone. These included nausea, vomiting, mouth soreness and low blood counts. Three people in the cisplatin group died of complications possibly linked to the drug, compared with no treatment-related deaths in those receiving only radiation. Forastiere thinks cisplatin's harshness may explain the disappointing results. "Maybe the postoperative population just doesn't tolerate the treatment as well," she says. Even so, the researchers aren't ready to call the combination therapy a total bust. Roughly a third of their patient population hadn't been followed for two years when the data were collected last October. The first 24 months are a critical time for the return of tumors, and it's the period when most patients suffer relapses. However, she says, even if the drug performs better in these people than it did in the others, the overall results are unlikely to change markedly. The researchers are considering lower doses of cisplatin to make it more palatable to patients. They're also looking to newer, high-tech cancer drugs that might supplement radiation, ones that target cancer cells directly. "We're just going to have to wait and be patient to see if [cisplatin plus radiation] is really effective," Cooper says. "But whether it is or it isn't, the concept that using modest doses of chemotherapy to enhance the effectiveness of radiation seems to be a valid paradigm." Tongue Cancer Still Rare, but Rates Are Increasing-(Reuters Health-19/03/2002) The incidence of tongue cancer, although still rare, increased 60% over the last three decades in US adults under age 40, according to a new report. "Because incidence rates of overall head and neck cancer have remained stable and have even shown a declining trend since the 1970s, the increase in the number of young adult patients (with tongue cancer) is concerning," write co-authors Drs. Stimson P. Schantz and Guo-Pei Yu of New York Medical College in Manhattan. While factors responsible for the increase remain unknown, the authors suggest increasing use of marijuana as well as smokeless tobacco products like chewing tobacco among this population group may be to blame. Another possible cause may be infections with |
