Influence of possible predictor variables on the outcome of primary oral squamous cell carcinoma: a retrospective study of 392 consecutive cases at a single centre.

The successful treatment of oral squamous cell carcinoma (OSCC) depends on the treatment strategy. The prognosis is most often linked to the stage at initial presentation, but the effect of patient-related parameters on overall survival remains uncertain. In this study, 392 consecutive cases of OSCC seen between 2007 and 2013 at a single centre were analyzed retrospectively. Overall survival was assessed and univariate and multivariate Cox proportional hazards regression was used to identify associations between possible tumour-specific and patient-related variables and survival. The 5-year overall survival rate of the 392 patients (T stage 1-4) was 62.5%. Univariate analysis showed that sex, age, T stage, N stage, Union for International Cancer Control (UICC) stage, American Society of Anesthesiologists (ASA) status, operating time >400min, and length of in-patient stay >15 days were significantly associated with overall survival (all P<0.05). Tumour location, alcohol abuse, and smoking were found not to have a significant influence (all P>0.05). Age, T, N, and M stages, UICC stage, residual tumour status, recurrence, ASA status, and operating time >400min were found to have a significant influence on overall survival in the multivariate analysis (each P<0.05). These findings confirm that postoperative survival does not depend only on tumour-related characteristics. ASA status needs to be considered in treatment planning, as it significantly predicts patient survival.