Long-Term Outcomes After Elective Contralateral Neck Dissection for HPV-Related Oropharyngeal Cancer.

OBJECTIVE: Patients with human papillomavirus (HPV)-related oropharyngeal squamous cell carcinoma (OPSCC), particularly of the base of tongue, have a high rate of occult nodal disease in the contralateral neck. The risk of failure in the contralateral neck is reduced with elective treatment. The optimal treatment strategy to minimize treatment-related toxicity while preserving regional control in the contralateral neck has not been elucidated. STUDY DESIGN: Cross-sectional study of patients who underwent elective contralateral neck dissection as part of primary surgical treatment for HPV-related OPSCC between January 2002 and December 2018. SETTING: Tertiary care center. METHODS: Patients who underwent elective contralateral neck dissection as part of primary surgical treatment for HPV-related OPSCC between January 2002 and December 2018 were selected for inclusion. Long-term patient-reported functional outcomes were assessed via telephone at the time of data collection. RESULTS: In total, 64 patients met the criteria for inclusion with a median follow-up of 58.5 months. In total, 56 patients (88%) had a primary cancer within the base of tongue or glossotonsillar sulcus. In total, 12 patients (19%) were found to have occult nodal metastasis in the contralateral neck, of whom 9 received adjuvant contralateral neck radiation. None of the patients who had node-negative contralateral neck dissections went on to receive radiation in the contralateral neck. Two patients (3%) recurred locally, two patients (3%) developed ipsilateral regional recurrence, and four patients (6%) developed distant metastasis. There were no regional recurrences within the contralateral neck. Five-year progression-free survival was 82.0%, whereas 5-year locoregional control was 93.0%. The mean Neck-Dissection Impairment Index was 94.4 with a median interval time of 92 months after surgery. CONCLUSION: Elective contralateral neck dissection in patients with HPV-related OPSCC provides excellent regional control with minimal long-term functional impairment, and most patients can be spared contralateral neck radiation without compromising oncologic outcomes. This may decrease long-term toxicity related to bilateral neck irradiation.