According to an article recently published in The Lancet, a shorter overall schedule of radiation therapy involving delivery of treatment 6 times per week appears superior to the conventional 5 times per week in patients with locally advanced head and neck cancer.
The term head and neck cancer refers to any number of cancers that may occur in the head and/or neck region. These may include cancers of the tongue, mouth, salivary glands, pharynx, larynx, sinus and other sites located in the head and neck area. Treatment options depend upon the stage, or extent, or cancer, but often include surgery, radiation therapy and/or chemotherapy. The surgical removal of advanced cancer may leave a patient debilitated or severely disfigured; therefore, radiation and chemotherapy regimens are being studied in order to produce optimal long-term outcomes without the side effects of surgery. Radiation therapy is the primary therapy for patients with cancers of the glottic and supraglottic areas, pharynx and oral cavity. Radiation therapy, like chemotherapy, is most effective when delivered over a short period of time, so as not to allow cancer cells recover between deliveries. However, shorter periods of time may not allow for recovery of normal tissue and a balance has to be achieved between cancer cell kill and tolerable side effects.
Recently, researchers from Norway and Denmark conducted a clinical trial comparing different schedules and doses of radiation therapy for treatment of locally advanced head and neck cancer. This trial included over 1,400 patients with cancer that had spread to local lymph nodes (lymph node metastasis). Patients were treated with a schedule of either 39 days or 46 days of radiation therapy. Patients treated for 39 days received radiation 6 times per week (accelerated radiation), and patients treated for 46 days received radiation 5 days per week. Over the course of the entire treatment, patients in both groups received the same overall radiation dose and number of radiation treatments. Approximately 5 years following therapy, cancer near the site of origin did not spread or recur in 70% of patients treated with accelerated radiation, compared to 60% of patients treated with the longer schedule. Death that was caused by cancer occurred in 27% of patients treated with accelerated radiation, compared to 34% of patients treated with the longer schedule. However, overall survival was the same between both groups. A greater proportion of patients with cancer of the larynx were able to preserve their voice in the accelerated group (80% versus 68%). The different schedules of radiation did not affect lymph node metastasis. Early side effects occurred more frequently in the group of patients treated with accelerated radiation; however, these side effects were reversible, and there were no additional side effects that occurred later in treatment.
The researchers concluded that accelerated radiation therapy involving treatment administration 6 times per week, versus the conventional 5 times per week appears to improve anti-cancer responses, reduce deaths caused by cancer and improve rates of voice preservation in patients with locally advanced head and neck cancer. The authors recommended that administering radiation 6 times per week should be considered as a standard approach for treatment of this group of patients. Patients with locally advanced head and neck cancer who are to undergo radiation therapy as their primary treatment may wish to speak with their physician about the risks and benefits of accelerated radiation therapy.
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Reference: Overgaard J, Hansen HS, Specht L, et al. Five Compared with Six Fractions per Week of Conventional Radiotherapy of Squamous-Cell Carcinoma of Head and Neck: DAHANCA 6and7 Randomised Trial.
The Lancet. 2003;362:933-940.