) Standard radiation for advanced head and neck malignancies typically causes permanent xerostomia that is cited by patients as a major cause of reduced quality of life. In an effort to reduce radiation-induced xerostomia, we have initiated a study of the feasibility of sparing major salivary gland tissue while adequately irradiating the targets in patients requiring comprehensive, bilateral neck irradiation. For this purpose, we utilize computed-tomography based conformal, 3-dimensional (3D) radiation planning and treatment tools. We have achieved adequate target coverage and significant sparing of parotid gland tissue. Significant saliva flow preservation has been achieved. The goal of this work is to improve long-term quality of life following radiation.
Our aims i n the proposed study are to assess the extent of improvement in the quality of life in patients treated using these techniques compared with s i milar patients treated with standard techniques, to assess whether improvements in xerostomia and quality of life are related to the amount of saliva flow retained following radiation, and to determine the relationships between the volumes irradiated and the doses delivered to the parotid glands and their function following radiation. The results will establish the methodology for conducting randomized, larger trials that are required to test the extent to which the techniques we have utilized improve quality of life while preserving tumor control rates compared with standard techniques, and to determine if such trials are worth undertaking.
