Survival and clinicopathological characteristics of cT4b oral squamous cell carcinoma based on different treatment modalities A single-center retrospective study

Introduction: Primary surgical treatment for oral squamous cell carcinoma (OSCC) is reserved for T1 to T4a tumors, but not for T4b tumors, according to the present National Comprehensive Cancer Network clinical practice guidelines. In this retrospective study, we aimed to determine the association between the clinicopathological characteristics and different treatment modalities for T4b OSCC based on whether patients received primary surgical treatment. Therefore, we conducted a survival analysis based on different treatment modalities. Methods: This retrospective cohort study enrolled 125 patients with clinical stage T4b OSCC who received treatment and were followed up at Changhua Christian Hospital between January 1, 2008 and December 31, 2018. Results: Overall, 81 patients received primary surgical treatment and 44 received primary nonsurgical treatment. Comparison of the clinicopathological characteristics between those who did and did not undergo surgery revealed no significant differences in age at tumor diagnosis, tumor location, clinical N stage, and involved tumor area based on computed tomography or magnetic resonance imaging, or stratified Charlson Comorbidity Index scores. In the survival analysis, Kaplan-Meier curves revealed that patients who received treatment modalities including surgery exhibited better survival than those who received treatment modalities that did not include surgery. Conclusions: In the present study, patients with T4b OSCC treated with primary surgery had a better overall survival rate than those who received nonsurgical treatment. In the future, it will be necessary for clinicians worldwide to report the treatment outcomes of patients with T4b OSCC based on the common criteria.