Time to Recurrence Associated With Poor Prognosis in Japanese Oral Squamous Cell Carcinoma Patients

Purpose Recurrence in oral squamous cell carcinoma (OSCC) is not rare. Due to lack of studies assessing characteristics of recurrent OSCC, including time to recurrence and outcomes, we sought to investigate its characteristics, time to recurrence, and outcomes in Japanese OSCC patients. Methods This study was a nonrandomized retrospective cohort study in a tertiary referral centre. It included 208 (117 men and 91 women) patients with recurrent oral cancer who underwent major curative surgery in the Department of Oral and Maxillofacial Surgery at Kobe University Hospital between January 1999 and April 2017. The outcomes were disease-specific survival (DSS) and overall survival (OS). Results In multivariable Cox proportional hazards analysis, the time to recurrence (hazard ratio [HR] 3.55, 95% confidence interval [CI] 1.69–6.63; P = 0.001), extranodal extension (ENE, HR 2.72, 95% CI 1.51–4.89; P = 0.001), and high T stage (HR 2.00, 95% CI 1.01–3.97; P = 0.046) were independent predictors of DSS. The time to recurrence (HR 3.29, 95% CI 1.82–5.96; P < 0.001) and ENE (HR 2.64, 95% CI 1.52–4.56; P = 0.001) were independent predictors of OS. Conclusion Time to recurrence, extranodal extension, and higher T stage were independent prognosis predictors in OSCC.