IntroductionIn early-stage oral tongue squamous cell carcinoma (OTSCC), elective neck dissection (END) is recommended when occult lymph node metastasis is suspected; however, there is no unanimous consensus on the risks and benefits of END in such cases. The management of clinically node-negative (cN0) OTSCC remains controversial. This study, therefore, aimed to evaluate the efficacy of END and its impact on the quality of life (QoL) of patients with cN0 OTSCC.Methods and analysisThis is a prospective, multicentre, nonrandomised observational study. The choice of whether to perform END at the same time as resection of the primary tumour is based on institutional policy and patient preference. The primary endpoint of this study is 3-year overall survival. The secondary endpoints are 3-year disease-specific survival, 3-year relapse-free survival and the impact on patient QoL. Propensity score-matching analysis will be performed to reduce selection bias.Ethics and disseminationThis study was approved by the Clinical Research Review Board of the Nagasaki University. The protocol of this study was registered at the University Hospital Medical Information Network Clinical Trials Registry. The datasets generated during the current study will be available from the corresponding author on reasonable request. The results will be disseminated internationally, through scientific and professional conferences and in peer-reviewed medical journals.Trial registration numberUMIN000027875.

AimThe post‐treatment quality of life (QOL) of patients with cancer has become an important issue owing to significant improvements in the outcomes of cancer treatment. The oral cavity has not only life‐sustaining functions but also important social functions, including talking. Thus, many reports have assessed the post‐treatment QOL of patients with oral cancer. However, the sample sizes in most studies were insufficient to control for potential confounding variables. Additionally, previous studies have indicated that racial/ethnic differences may be associated with health‐related QOL. Thus, this study aimed to clarify factors influencing post‐treatment QOL using multiple regression analysis in a large number of Japanese patients with tongue cancer.MethodsIn total, 106 patients with tongue cancer were recruited from the oral surgery departments of three university hospitals sharing a common treatment plan for tongue cancer. QOL was evaluated using the University of Washington Quality of Life Questionnaire, and depressive tendencies were assessed using the Self‐rating Depression Scale (SDS).ResultsNeck dissection was most widely associated with physical and socio‐emotional QOL. Reconstruction, radiotherapy, and higher T‐stage and SDS scores were the second most widely associated factors with QOL. Interestingly, a higher SDS score was negatively related only to socio‐emotional factors. Furthermore, only SDS scores were associated with the general QOL.ConclusionThis study suggested that the physical and socio‐emotional QOL was widely affected by neck dissection, reconstruction, radiotherapy, T‐stage, and SDS scores, whereas the general QOL was affected only by SDS scores. These findings should be considered when treating patients with oral cancer.