Unilateral vs Bilateral Transoral Robotic Surgery for HPV-Positive Tonsillar Squamous Cell Carcinoma

Importance: The palatine tonsil is the most common subsite of human papillomavirus (HPV)-related oropharyngeal squamous cell carcinoma (SCC). There is debate on how to manage the contralateral clinically uninvolved tonsil in patients undergoing a primary surgical approach via transoral robotic surgery (TORS). Objective: To assess postoperative complications, functional outcomes, contralateral tonsil second primary rates, and survival in patients undergoing unilateral vs bilateral TORS with pathology-guided adjuvant treatment. Design, Setting, and Participants: A retrospective cohort study was carried out in a quaternary care academic medical center. All consecutive unilateral tonsillar patients with SCC undergoing TORS as primary treatment from June 2016 to July 2023 were included. Analysis was conducted between October 1, 2024, and January 1, 2025. Exposure: Unilateral TORS (ipsilateral radical tonsillectomy) vs bilateral TORS (ipsilateral radical tonsillectomy and contralateral extracapsular tonsillectomy). Main Outcomes: The primary outcome measure was rate of postoperative oropharyngeal hemorrhage. Secondary outcome measures included postoperative emergency department (ED) visit/hospitalization rate, time to nasogastric tube (NGT) removal, rate of discharge with an NGT tube, G-tube dependence rates, second primary rates in the contralateral tonsil, length of stay, and 2-year and 5-year disease-free survival (DFS) and overall survival (OS). Results: A total of 158 (106 unilateral, 52 bilateral TORS) patients with HPV-associated tonsillar SCC were evaluated, including 18 women and 139 men with a mean (SD) age of 60 (10) years. There were clinically meaningful differences in oropharyngeal hemorrhage rates (7% vs 15%; percent difference, -7.8; 95% CI, -18.8% to 3.2%), 30-day ED visit/hospitalization rates (9% vs 21%; percent difference, -11.7%; 95% CI, -24.1 to 0.7), and median length of stay (2 vs 3 days) for unilateral and bilateral TORS, respectively. Swallowing outcomes, DFS, and OS were not significantly different between the 2 groups. A total of 3 patients (1.9%) had a second primary tumor in the contralateral tonsil, including 2 metachronous primary tumors in the unilateral group (1.8%) and 1 synchronous primary tumor incidentally removed at the time of surgery in the bilateral group (1.9%). Conclusions and Relevance: This cohort study found that omission of contralateral elective extracapsular tonsillectomy in HPV-positive SCC was safe and associated with a trend toward lower posttonsillectomy hemorrhage, postoperative ED visits for pain control, and hospital length of stay without compromising survival. Prophylactically resecting the contralateral tonsil may add patient harm without any clear benefits.