Predictors of contralateral-bilateral nodal disease in oropharyngeal cancer: A National Cancer Data Base Study

Background: Oropharyngeal squamous cell carcinoma (SCC) frequently presents with cervical metastasis. Roles of human papillomavirus (HPV) status, among other factors, on laterality are elusive. Methods: The National Cancer Database was reviewed for oropharyngeal SCC diagnosed from 2010-2014. Predictors of clinically evident contralateral or bilateral nodal disease were identified. Results: A total of 15 517 patients with oropharyngeal SCC met criteria. The majority was HPV-positive. Histologically poorly differentiated tumors were more frequent in the HPV-positive group (55.7% vs 37.6%; P <.001). By incidence, there was no statistical difference in contralateral or bilateral nodal disease between HPV-positive and HPV-negative patients (14.2% vs 14.5%, respectively; P =.769). On multivariable analysis, notable predictors of contralateral or bilateral nodal disease included HPV-positivity (odds ratio [OR] 1.26; 99% confidence interval [CI] 1.10-1.44), base of tongue (BOT) location (OR 2.15; 99% CI 1.88-2.45), poorly differentiated tumor (OR 1.72; 99% CI 1.20-2.46), and T4 classification (OR 6.65; 99% CI 5.34-8.28). Conclusion: Patients with HPV-associated oropharyngeal SCC have increased likelihood of contralateral or bilateral nodal disease. Tumor grade, tumor location, and tumor size are also independent predictors.