Nodal Metastases in Stage 3 Head and Neck Melanoma: Patterns of Metastases and Patterns of Failure.

OBJECTIVE:Stage 3 patients with clinically positive nodal metastasis are treated with therapeutic neck dissection and adjuvant systemic therapy. The aim of our study was to examined the predictability of pre-operative CT as a nodal drainage assessment tool. METHODS:Retrospective review of all patients with clinically positive head and neck cutaneous melanoma between 2010 and 2019. Clinical disease was diagnosed as radiological suspicious, biopsy-proven node. A pre-operative CT evaluation for nodal metastasis was compared to pathology report. RESULTS:A total of 53 patients were included. Forty patients (75.5%) were males with a mean age of 59 (SD 15.52). The majority of patients (26.4%) had an unknown primary site. The most common sites for primary were the cheek in eight patients (15.1%) followed by forehead (9.4%) and lateral neck (9.4%). Preoperative CT predicted nodal disease in 84.6% of cases. The primary region that mainly failed from the previously described clinical prediction was the upper anterior neck with 83.3% parotid involvement. A total of 10 patients (18.9%) were diagnosis with non-clinical nodes on pathology with a median non-clinical node of 1 (range 1-2). Of them, 9 (90%) were in the same clinical levels detected by CT. Pre-operative CT was associated with a neck level accuracy of 98.1%. CONCLUSION:Stage 3 head and neck melanoma with clinically positive nodal metastasis that are eligible for an adjuvant systemic treatment, may benefit from a highly selective neck dissection according to their pre-operative imaging studies. This should be further evaluated in a large-scale clinical trial. LEVEL OF EVIDENCE:3 Laryngoscope, 2024.