Incidence and distribution of contralateral lymph node metastasis associated with human papillomavirus-related oropharyngeal squamous cell carcinoma

Objective To analyse the rate of contralateral nodal metastasis in human papillomavirus (HPV)-associated oropharyngeal carcinoma and identify the patient cohorts that would benefit from bilateral neck treatment.Methods A retrospective cohort review was performed on 110 HPV-positive oropharyngeal carcinoma patients who underwent transoral robotic surgery and bilateral neck dissections from 2012 to 2022. The primary outcome was to investigate the pathological incidence and location of contralateral neck node metastasis.Results The contralateral nodal disease rate was 12.7 per cent (n = 14), of which 2 patients (2 per cent) were occult findings, with comparable results between tongue base and tonsil sub-groups. The most commonly involved contralateral nodal station was level II (11 of 110 patients, 10 per cent). The presence of extra-nodal extension and multiple ipsilateral positive nodes was associated with increased risk of contralateral nodal disease.Conclusion The incidence of contralateral nodal and occult disease in the studied cohort is low. The characteristics of patients who may benefit from bilateral neck treatment were demonstrated.