Comparison of the American Joint Committee on Cancer N1 versus N2a nodal categories for predicting survival and recurrence in patients with oral cancer: Time to acknowledge an arbitrary distinction and modify the system.

BACKGROUND: We hypothesized that pathological N1 (pN1) and N2a (pN2a) nodal disease portend a similar prognosis in patients with oral cancer. METHODS: An international multicenter study of 739 oral squamous cell carcinoma (SCC) patients with pN1 or pN2a stage disease was conducted. Multivariable analyses were performed using Cox proportional hazard models to compare locoregional failure, disease-specific survival (DSS), and overall survival (OS). Institutional heterogeneity was assessed using 2-stage random effects meta-analysis techniques. RESULTS: Univariate analysis revealed no difference in locoregional failure (p = .184), DSS (p = .761), or OS (p = .475). Similar results were obtained in adjusted multivariable models and no evidence of institutional heterogeneity was demonstrated. CONCLUSION: The prognosis of pN2a and pN1 disease is similar in oral SCC suggesting these categories could be combined in future revisions of the nodal staging system to enhance prognostic accuracy. However, these results may reflect more aggressive treatment of N2a disease; hence, we caution against using these data to deintensify treatment.