Lymph node yield from neck dissection in HPV-associated 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 vs. ≥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.