Immunonutrients for radiation-induced oral mucositis in head and neck cancer: current evidence and future perspectives.

Radiation-induced oral mucositis (RIOM) is one of the most common and severe complications in patients with head and neck malignancies undergoing radiotherapy or chemoradiotherapy, with an incidence of 80-100%. More than half of patients develop severe RIOM (grade 3-4), resulting in intense pain, dysphagia, and malnutrition, which significantly impairs quality of life. However, conventional nutritional support primarily provides basic nutrients and lacks immunomodulatory effects. Immunonutrition, characterized by a favorable safety profile and good tolerability, not only meets nutritional requirements but also modulates immune responses, attenuates inflammation, and supports mucosal barrier repair. It has been shown to enhance patients' tolerance and response to radiotherapy and chemotherapy, thereby improving clinical outcomes. Given that inflammation, oxidative stress, and mucosal barrier disruption are central to the pathogenesis of RIOM, these properties suggest that immunonutrition may play a beneficial role in its prevention and management. This narrative review summarizes the current evidence on immunonutrition in RIOM and explores its potential as a therapeutic approach for its prevention and treatment, with the aim of providing useful insights for improving patient quality of life and clinical outcomes.