Residual nodal disease in patients with advanced-stage oropharyngeal squamous cell carcinoma treated with definitive radiation therapy and posttreatment neck dissection: Association with locoregional recurrence, distant metastasis, and decreased survival

Background: Oropharyngeal squamous cell carcinoma (OPSCC) is increasing in frequency. We reviewed patients with advanced-stage OPSCC treated with chemoradiation to assess the impact of residual neck disease on survival. Methods: We reviewed 202 patients with OPSCC between 1990 and 2010 treated with primary chemoradiation followed by neck dissection. Imaging was analyzed using RECIST (Response Evaluation Criteria In Solid Tumors) 1.1 criteria. Survival was evaluated using both univariate and multivariate analyses. Results: Overall survival at 5 years was 89%. Forty-two patients (21%) had residual disease in the neck (pN+). pN+ was associated with greater locoregional recurrence (LRR) and distant metastasis (DM) and decreased survival. No clinicopathologic factors were predictive of pN+. Contrasted posttreatment CT had low sensitivity and specificity. Conclusions: In advanced OPSCC pN+, patients have higher rates of LRR and DM. Neither clinicopathologic factors nor posttreatment imaging was predictive of pN+, although increased use of modern imaging may reduce the rate of negative neck dissections.