Concurrent chemoradiotherapy induces body composition changes in locally advanced head and neck squamous cell carcinoma: Comparison between oral cavity and non‐oral cavity cancer

Few prospective cohort trials have evaluated the difference in treatment‐interval total body composition (TBC) changes assessed by dual‐energy X‐ray absorptiometry (DXA) between two patient subgroups with locally advanced head and neck squamous cell carcinoma (LAHNSCC) receiving concurrent chemoradiotherapy (CCRT): oral cavity cancer with adjuvant CCRT (OCC) and non‐oral cavity with primary CCRT (NOCC). This study prospectively recruited patients with LAHNSCC. Clinicopathological variables, blood nutritional/inflammatory markers, CCRT‐related factors, and TBC data assessed by DXA before and after treatment were collected. Multivariate lin-ear regression analysis identified the factors associated with treatment‐interval changes in body composition parameters, including lean body mass (LBM), total fat mass (TFM), and bone mineral content (BMC). A total of 127 patients (OCC (n = 69) and NOCC (n = 58)) were eligible. Body composition parameters were progressively lost during CCRT in both subgroups. Extremities lost more muscle mass than the trunk for LBM, whereas the trunk lost more fat mass than the extremities for TFM. BMC loss preferentially occurred in the trunk region. Different factors were independently correlated with the interval changes of each body composition parameter for both OCC and NOCC subgroups, particularly mean daily calorie intake for LBM and TFM loss, and total lymphocyte count for BMC loss. In conclusion, treatment‐interval TBC changes and related contributing factors differ between the OCC and NOCC subgroups.