Long-Term Oncologic Outcomes of Induction Chemotherapy Followed by Surgery Versus Upfront Surgery in Oral Cavity Squamous Cell Carcinoma

Background: The optimal role of induction chemotherapy (IC) in the management of oral cavity squamous cell carcinoma (OCSCC) remains controversial. This study compared oncologic outcomes between IC followed by surgery and concurrent chemoradiotherapy (CCRT) and upfront surgery followed by adjuvant CCRT. Methods: We retrospectively analyzed 98 patients with OCSCC treated between 2011 and 2017. Overall survival (OS), cancer-specific survival (CSS), and local control (LC) were evaluated using Kaplan–Meier survival analysis and Cox proportional hazards models to identify prognostic factors. Results: Fifty patients received IC and 48 underwent upfront surgery. With a median follow-up of 77.8 months, no significant differences in OS, CSS, or LC were observed between treatment groups (OS: HR 1.31, p = 0.415; CSS: HR 1.36, p = 0.421; LC: HR 1.29, p = 0.475). Positive surgical margins independently predicted inferior OS, CSS, and LC, while extracapsular spread was independently associated with inferior CSS. Although tumor downstaging was frequently observed after IC, it did not translate into survival benefit. Conclusions: IC followed by surgery was associated with no statistically significant differences in oncologic outcomes compared with upfront surgery followed by adjuvant CCRT. Prognosis was primarily determined by pathological risk factors rather than treatment sequence.