Neck metastases in oropharyngeal cancer: Necessity and extent of bilateral treatment

BACKGROUND: Bilateral neck treatment in oropharyngeal squamous cell carcinoma (OPSCC) is controversial. This study determined the rate of bilateral neck metastases in OPSCC and formulated a neck treatment algorithrm for OPSCC. METHODS: In all, 212 consecutive patients with OPSCC underwent ipsilateral level I-V and contralateral I-III or I-V neck dissections. Pathology results were used to identify factors predicting bilateral neck metastases. RESULTS: A total of 171 patients (81%) had ipsilateral and 41 patients (24%) bilateral neck metastases. Multivariate logistic regression found cT4 and ≥cN2a significantly associated with contralateral neck metastases (p < .05). However, tumor site was not predictive (p > .05). High-risk pathology features predicted contralateral neck disease (p < .05). cN0 and cN1 necks were unlikely to harbor disease in level V (<5%). Both 2- and 5-year contralateral neck recurrence rates were 1% and 2%. CONCLUSIONS: Bilateral neck disease in OPSCC is more common than once thought. Patients with OPSCC with cT4 or cN2a+ would benefit from bilateral neck treatment. Posttreatment high-risk features should guide treatment escalation.