Pretreatment body mass index as a prognostic predictor in patients with oral squamous cell carcinoma

Objectives To evaluate whether low body mass index (BMI) is a potential adverse prognostic factor in patients with oral squamous cell carcinoma (OSCC). Material and methods This cross-sectional study included 320 patients with OSCC who underwent therapeutic surgical treatment in Taiwan. The pretreatment BMI was measured as a common indicator of the pretreatment nutritional status to calculate the overall survival in Kaplan-Meier method. The adverse histopathological features of margin status, depth of invasion (DOI), lymphovascular invasion (LVSI), perineural invasion (PNI), and extranodal extension (ENE) were analyzed using the Cox regression model. Results Low BMI (underweight), DOI > 5 mm, and ENE were identified as detrimental prognostic factors. On multivariate Cox regression analysis, the low BMI group (odds ratio [OR] = 1.683; 95% confidence interval [95% CI] 1.116-2.539;P= 0.022), DOI > 5 mm (OR = 2.399; 95% CI 1.459-3.943;P= 0.001), and ENE (OR = 2.467; 95% CI 1.540-3.951;P= 0.000) yielded reduced survival rate. Conclusions The lower BMI had an important and significant effect on the survival of patients with oral cancer and their surgical outcomes. In addition to the adverse histopathological features, a DOI > 5 mm and positive ENE were also identified as the most important prognostic factors.