Contralateral neck failure in oral tongue cancer: Outcomes from two centers using predefined treatment criteria.

BACKGROUND The objective was to determine the incidence of, and factors associated with contralateral neck failure (CNF) in oral tongue squamous cell carcinoma (OTSCC). METHODS Consecutive patients with OTSCC between 2007 and 2016 were included. The predefined policy of the contralateral neck included neck dissection (ND) where the primary tumor extended/crossed midline or the contralateral neck was involved; and elective nodal irradiation (ENI) where the primary tumor was ≤1 cm from midline/2 cm from tip. RESULTS This study included 258 patients. ND was ipsilateral 169 (66%) and bilateral 33 (13%). Fifty-five patients (21%) received ENI to the undissected contralateral neck. CNF occurred in 19 patients (7%) and was similar by treatment received. Utilizing this approach, we observed higher rates of CNF with increasing N classification, perineural invasion, extracapsular extension, and depth of invasion ≥6 mm. CONCLUSIONS Using our institutional policy of treatment to the contralateral neck, a low rate of CNF (≤10%) was observed.