Impact of Low Skeletal Muscle Mass on the Prognosis of Patients with Head and Neck Cancer Treated Nonsurgically

Introduction: Sarcopenia, characterized by low skeletal muscle mass, and the outcome of cancer therapy are closely related based on recent research. This study aimed to evaluate the correlation between skeletal muscle mass and prognosis in head and neck cancer (HNC) patients. Methods: In this study, 51 male patients with HNC treated nonsurgically between January 2016 and April 2018 at Shinshu University Hospital were evaluated. Skeletal muscle mass was assessed using bioelectrical impedance analysis, and the skeletal mass index (SMI) was calculated to classify the patients. Results: The low-SMI group had a significantly worse overall survival (OS) than the normal-SMI group (3-year OS: 72.0% vs. 93.0%, p = 0.014), and there was a trend toward worse progression-free survival (PFS) in the low-SMI group (3-year PFS: 49.6% vs. 79.3%, p = 0.064). Multivariate analysis also showed that low SMI (p = 0.04) and severe N stage (p = 0.009) were significantly associated with poorer OS. Conclusion: The pretreatment assessment of SMI using bioelectrical impedance analysis is useful for identifying patients with poor prognoses. To improve the treatment outcome in HNC, we need to think of the intervention, such as cancer rehabilitation and nutritional support, during or before treatment, especially for patients with low SMI. ORL