Malnutrition and radiation therapy in head and neck cancers, a systematic review on reported definitions and associated factors.

Radiation therapy is a major treatment in head and neck cancers that can induce mucositis, pain, and dysgeusia that could impair oral intake and lead to weight loss and malnutrition. Intensity modulation has diminished toxicity of radiation therapy. We performed a review to assess the rate of malnutrition and how malnutrition was defined across cohorts of patients undergoing modern curative radiation therapy. We performed a systematic review of prospective cohorts to assess how was defined malnutrition and severe malnutrition as binary outcomes and to report their rates depending on their definition. We screened 250 papers and included 27 papers in the review. Only two studies reported malnutrition using the Global Leadership Initiative on Malnutrition (GLIM) criteria, and the most reported criteria were PG SGA (patient-graded subjective global assessment) B or C and weight loss above 10%. The most frequently reported factors associated with malnutrition were concomitant chemotherapy, tumoral stage, and tumor site. Our review highlighted the major heterogeneity of the reporting of patient's nutritional state across cohorts of head and neck cancers treated by modern curative radiotherapy. Using consensual definition of malnutrition would help to provide stronger evidence on preventive enteral nutrition as well as the causes and consequences of malnutrition in head and neck cancers.