Ideal doses of IMRT defined to reduce treatment side effects for head and neck cancerOctober 19, 2005Results from a University of Pittsburgh study evaluating intensity modulated radiation therapy (IMRT) for head and neck cancer determined the ideal doses for lessening treatment side effects. The findings were presented today at the 47th Annual Meeting of the American Society for Therapeutic Radiology and Oncology (ASTRO) in Denver. "Despite major advances in chemotherapy and radiation for the treatment of head and neck cancers, many patients continue to suffer debilitating side effects that greatly impact their quality of life," said Dwight E. Heron, M.D., study co-author and associate professor of radiation oncology, University of Pittsburgh School of Medicine and director of radiation oncology, University of Pittsburgh Medical Center. "While these high-energy beams are targeted to the tumor site as precisely as possible, they often inadvertently injure healthy tissue that surrounds the tumor site, limiting the doses of radiation that can be used to effectively destroy cancer cells. With this study, we sought to discover whether tightly focused radiation beams, such as those provided by IMRT, would make a difference in the severity of side effects associated with treatment and found a distinct dose-response relationship in the oral cavity of patients treated with IMRT in addition to chemotherapy." In the study, 70 patients with head and neck cancer were treated with IMRT using the Eclipseâ Planning System, Varian Medical Systems and chemotherapy. Patients were treated from April 2002 through September 2004 and were evaluated for grade level of oral mucositis, or inflammation, based on the volume of IMRT dose administered. Oral mucositis not only causes pain, but also can affect speech, the ability to eat or drink and to take oral medication. Patients with severe cases may require tube feeding. Results indicated that the severity of side effects, or the grade of oral mucositis, was directly correlated with the volume of the radiation dose administered to the oral cavity, and the researchers defined an ideal dose volume of IMRT at which the incidence of acute oral mucositis was lessened. "We found that if we constrain the dose of IMRT, we reduce the toxic effects of treatment," said Dr. Heron. "These results are encouraging evidence that head and neck cancer patients can benefit from IMRT at specific doses. With more homogenous and conformal treatment, head and neck cancer patients may be spared side effects from standard radiotherapy that can be significant." During radiation therapy, high-energy beams are aimed at cancer cells to destroy them by permanently damaging their underlying genetic material. Unlike standard radiation therapy, IMRT administers a radiation field that consists of several hundred small beams of varying intensities that pass through normal tissue without doing significant damage, but converge to give a precise dose of radiation at the tumor site. IMRT can potentially limit the adverse side effects from radiation while increasing the intensity of doses that can be given to effectively destroy cancer cells. IMRT is combined with a process called inverse treatment planning to determine the best way to treat a patient. It relies on CT (computed tomography) data from patients that is processed and analyzed by a complex computer system to produce the ideal radiation dose distribution for that patient. University of Pittsburgh Medical Center |
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| Related Head And Neck Cancer Current Events and Head And Neck Cancer News Articles New laryngoscope could make difficult intubations easier A new tool developed by a Medical College of Georgia resident and faculty member may make it easier to place assisted breathing devices under difficult circumstances. Rare head and neck cancer linked to HPV, study finds An increase in cases of a rare type of head and neck cancer appears to be linked to HPV, or human papillomavirus, according to a new study from researchers at the University of Michigan Comprehensive Cancer Center. Curcumin may inhibit nicotine-induced activation of head and neck cancers Curcumin, the compound that gives curry powder its yellow/orange color, may inhibit the adverse effects of nicotine in patients with head and neck cancer who continue to smoke. Study finds 231 new genes associated with head and neck cancer A Henry Ford Hospital study has identified 231 new genes associated with head and neck cancer, one of the most deadly cancers responsible for 2.1 percent of all cancer deaths in the United States. U of T researchers create microchip that can detect type and severity of cancer U of T researchers have used nanomaterials to develop a microchip sensitive enough to quickly determine the type and severity of a patient's cancer so that the disease can be detected earlier for more effective treatment. Identification of highly radiosensitive patients may lead to side effect-free radiotherapy An international group of scientists has taken the first step on the road to targeting radiotherapy dosage to individual patients by means of their genetic characteristics. Adding cetuximab to chemotherapy reduces advanced lung cancer death risk by 13 percent Patients with advanced non-small cell lung cancer who are given cetuximab (Erbitux) in addition to chemotherapy are 13% less likely to die than those who receive chemotherapy alone, regardless of which chemotherapy drug cocktail is used, new research finds. They also experience slower disease progression and an increased chance of tumour shrinkage. Prevent periodontitis to reduce the risk of head and neck cancer Chronic periodontitis, a form of gum disease, is an independent risk factor for head and neck squamous cell carcinoma. This suggests the need for increased efforts to prevent and treat periodontitis as a possible means to reduce the risk of this form of cancer. Prodrug could help curb skin toxicity related to EGFR-inhibiting cancer drugs There may be a way around the harsh skin toxicity associated with a widely used cancer drug, according to a study published online this week in Cancer Biology and Therapy by researchers from City of Hope and the Kimmel Cancer at Jefferson. Budesonide is not beneficial for the treatment of diarrhea in metastatic melanoma patients Patients with stage III or IV melanoma taking ipilimumab and the oral steroid budesonide to reduce side effects did not have less diarrhea, a known side effect of ipilimumab. More Head And Neck Cancer Current Events and Head And Neck Cancer News Articles |
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