The relationship of nutritional status with anticancer immunity and its prognostic value for head and neck cancer.

Malnutrition has been reported to be associated with reduced survival and deficient anticancer immunity, and undernourishment is a frequent comorbidity in head and neck cancer (HNC) patients. In this study, we evaluated the relationship between nutritional status and immunologic factors, and its prognostic value for HNC. We retrospectively reviewed 212 HNC patients who had undergone a nutrition evaluation based on the Patient-Generated Subjective Global Assessment (PG-SGA) and curative radiotherapy (RT). The role of nutritional status in the prognosis of HNC and its correlation with anticancer immune response was assessed in HNC patients, and in the 4-nitroquinoline 1-oxide (4NQO)-induced tongue tumor animal model. Our data revealed that malnutrition (high PG-SGA scores) was significantly associated with more advanced disease, lower body mass index, lower RT completion rates, and reduced survival. Patients in the group with high PG-SGA scores had a higher neutrophil-to-lymphocyte ratio, higher proportion of myeloid-derived suppressor cells (MDSCs), and elevated IL-6 levels in the peripheral circulation. Patients with increased PG-SGA scores following treatment were more likely to developing locoregional failure. In the 4NQO-induced tumor model, nutritional supplementation decreased the rate of invasive tumor formation and attenuated the immune-suppressive microenvironment. Following ectopic tumor implantation in an immunocompetent host, nutrition supplements decreased tumor growth in association with attenuated MDSC recruitment and lower IL-6 expression. In conclusion, malnutrition by PG-SGA was associated with poor prognosis in HNC patients. Based on the data of HNC patients and the 4NQO-tumor model, adequate nutritional supplementation might improve the prognosis associated with augmented anticancer immunity.