The Oncological Outcome of Postoperative Radiotherapy in Patients with Node-Negative Early-Stage (T1/T2/N0) Oral Squamous Cell Carcinoma and Perineural Invasion: A Meta-Analysis
Karthik Rao, M. P. Sreeram, Remco de Bree, William M. Mendenhall, Primož Strojan, Göran Stenman, Antti Mäkitie, Alfons Nadal, Juan P. Rodrigo, Sweet Ping Ng, June Corry, Alessandra Rinaldo, Avraham Eisbruch, Alfio Ferlito
Abstract
Objective: To evaluate the impact of postoperative radiotherapy (PORT) on oncological outcomes in node-negative early-stage oral squamous cell carcinoma (OSCC) with perineural invasion (PNI). Methods: A systematic review and meta-analysis was conducted using the PubMed, EMBASE, and Scopus databases for the period from 2000 to 2024. Studies comparing PORT versus observation in pN0 early-stage OSCC with PNI were included. Oncological outcomes assessed included overall survival (OS), disease-free survival (DFS), and local control (LC). A random-effects model was used to calculate log odds ratios, and heterogeneity was assessed using tau2, chi2, and I2 statistics. Results: Seven retrospective studies comprising 522 patients (281 PORT, 241 no-PORT) were included. The 3-year overall survival (OS) was 86.3% in the PORT group compared to 71.1% in the no-PORT group (logOR = −1.03, p = 0.0012), while the 5-year OS was 88.1% versus 77.3% (logOR = −0.97, p = 0.0061). Disease-free survival (DFS) also favored PORT, with 3-year DFS at 86.3% versus 58.1% (logOR = −1.19, p < 0.001) and 5-year DFS at 86.3% versus 55% (logOR = −0.78, p = 0.003). Local control (LC) was higher in the PORT group, with 3-year LC rates of 89% compared to 72.2% in the no-PORT group (logOR = −1.13, p = 0.025). Conclusions: PORT significantly improves OS, DFS, and LC in node-negative early-stage OSCC with PNI as the sole adverse feature.