Lymph node yield from neck dissection in HPV-associated oropharyngeal cancer: Lymph Node Yield in Oropharyngeal Cancer

OBJECTIVES: To determine the influence of nodal yield during neck dissection on survival in surgically managed human papillomavirus (HPV)-associated oropharyngeal cancer. METHODS: The National Cancer Database was used to identify patients with HPV-associated tumor T1 to T2 oropharyngeal squamous cell carcinoma who underwent upfront surgery with or without adjuvant therapy. Patients were stratified by lymph node yield ( /=26 nodes). Multivariable Cox proportional hazards regression analysis was used to identify factors associated with overall survival. Models were stratified by pathologically positive node number. RESULTS: There were 2,554 patients identified with previously untreated T1 to T2 oropharyngeal squamous cell carcinoma who underwent resection of the primary tumor and neck dissection between 2010 and 2015. Fifty-two percent had zero to one pathologically involved lymph node. Among all study patients, lymph node harvest of >/=26 was not associated with survival when adjusted for relevant covariates (hazard ratio [HR] 0.70, 95% confidence interval [CI] 0.49-1.00). However, in patients with zero to one pathologically involved node, lymph node harvest of >/=26 was significantly associated with improved overall survival (HR 0.29, 95% CI 0.20-0.78). This survival benefit was lost in patients with two or more positive nodes (2-4 positive nodes: HR 0.89, 95% CI 0.52-1.51; 5 or more positive nodes: HR 1.01, 95% CI 0.47-2.20). CONCLUSION: For patients with surgically managed early T-stage HPV-associated oropharyngeal squamous cell carcinoma, lymph node yield was not associated with survival outcomes for patients with multiple positive lymph nodes. Those with a more limited burden of regional metastatic disease, however, may benefit harvest of at least 26 nodes during neck dissection. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:666-671, 2020.