Tumor stage and resection margins not the mandibular invasion determines the survival in patients with cancers of oro-mandibular region

IntroductionMandibular involvement in patients with oro-mandibular cancers is very common and is seen in up to 50% of the patients. Evidence suggests that preservation of uninvolved mandible does not reduce survival; however, evidence on effect of mandibular involvement on survival is sparse. We carried out this study to evaluate the effect of various factor including mandibular bone involvement on survival in patients with oro-mandibular cancers.Patients and methodsIn an open prospective study 51 patients with oral cancer undergoing mandibular excision were studied. Five year later, the survival information was collected on these patients from computerized database. Survival analysis was carried out by Kaplan Meier method and difference in survival was estimated using log-rank test. Predictors of survival were estimated using Cox proportional hazard model.ResultsThe 3 and 5 year survival was 62.6% and 46.9% respectively. Tumor stage (HR 8.7, p = 0.02), margin of surgical excision (HR 1.8, p = 0.007) and nodal stage (HR 2.2, p = 0.04) were found to be significant independent predictors of survival.ConclusionsIn absence of randomized controlled trial which are difficult to design and conduct, the results of present study shows that mandibular conservation may be carried out, even in presence of involved mandible if negative resection margins could be achieved.