Significance of perineural invasion in locally advanced bucco alveolar complex carcinomas treated with surgery and postoperative radiation ± concurrent chemotherapy.

Abstract

The purpose of this study was to evaluate prognostic factors, locoregional control, and survival in locally advanced bucco-alveolar complex cancers. A retrospective review of 83 patients treated between January 2009 and December 2012 with bucco-alveolar complex cancers was conducted. All patients had surgery and adjuvant radiotherapy with intensity-modulated radiotherapy (IMRT) with/without concurrent chemotherapy. Survival analysis was performed using Kaplan-Meier and multivariable Cox regression model. On univariate and multivariate analysis, perineural invasion (PNI) was found to be an independent adverse risk factor. Patients with PNI-positive disease had significantly worse 2-year disease-free survival (DFS), locoregional failure free survival, and overall survival (OS) as compared to patients with PNI-negative disease (P < 0. 001, 0.001 and < 0. 001) respectively. Compared with patients with PNI-negative disease, patients with PNI-positive disease had much worse outcome despite aggressive adjuvant treatment. It warrants escalation of therapy and modification in radiation portals to cover neural pathways in patients with PNI-positive disease.