Contralateral neck failure in lateralized oral squamous cell carcinoma

Background: Elective treatment of the contralateral clinically node-negative (cN0) neck is not routinely recommended for lateralized oral cavity squamous cell carcinoma (SCC). We sought to determine the failure rate in the untreated contralateral neck in patients with lateralized oral SCC undergoing treatment of the primary and ipsilateral neck and to identify any features placing patients at sufficient risk of contralateral regional failure to justify elective treatment.

Methods: We identified 688 patients with oral SCC undergoing curative surgery ± adjuvant therapy between 1985 and 2012 from a prospectively collected database. Patients with midline primaries and those undergoing bilateral neck treatment were excluded. The primary endpoint was isolated contralateral neck failure.

Results: Of 481 patients, 14 (2.9%) developed isolated contralateral neck recurrence, with median time to recurrence of 8 months. Patients with poorly differentiated tumours or pathologically proven ipsilateral nodal metastases were at significantly higher risk of contralateral failure (hazard ratio (HR) 3.6, 95% confidence interval (CI) 1.1-11.9, P = 0.037 and HR 4.6, 95% CI 1.5-13.8, P = 0.006 respectively). Presence of both of these factors conferred a 10% risk of contralateral failure.

Conclusion: Patients with lateralized oral SCC undergoing treatment of the primary tumour and ipsilateral neck have a low rate of isolated contralateral neck failure. Although poorly differentiated primaries and ipsilateral nodal metastases were predictors of contralateral recurrence, the risk remains relatively modest in this subset of patients suggesting close observation may be more appropriate than elective treatment. Our results support current recommendations for observation of the cN0 contralateral neck in lateralized oral SCC.