Approaches to regional lymph node metastasis in patients with head and neck mucosal melanoma

Mucosal melanomas in the head and neck region are most often located in the nasal cavity and paranasal sinuses. To the authors' knowledge, the prognostic effects of lymph node metastasis in patients with sinonasal mucosal melanoma (SNMM) have not been established. Therefore, the objective of the current study was to determine the effects of lymph node metastasis on survival.

The current study included 198 patients with SNMM who had been treated between 1985 and 2016 at The University of Texas MD Anderson Cancer Center in Houston. Patients' clinical and pathologic lymph node statuses were evaluated and characterized. A multivariate analysis was used to assess the associations between regional spread and survival outcomes.

Therapeutic neck dissection was performed in 23 patients with SNMM (11.6%). Regional disease recurrence occurred in 7 of the patients who had lymph node metastasis at the time of presentation (30.4%) and in 30 of those who had N0 disease at the time of presentation (17.1%) (P = .15). Metastasis to the contralateral lymph nodes was present in 7 patients (3.5%). The 5-year disease-specific survival rate was 66% in patients with lymph node spread compared with 45% in patients with N0 status (P = .04, log-rank test). A multivariate analysis demonstrated that distant metastasis was the only variable found to be independently associated with both overall survival (hazard ratio, 2.96; 95% confidence interval, 1.54-6.95 [P = .01]) and disease-specific survival (hazard ratio, 3.32; 95% confidence interval, 1.79-7.14 [P = 0.01]).

The results of the current study demonstrated that lymph node status in patients with SNMM was not a significant predictor of outcome. This finding, together with the low incidence of lymph node metastases in patients with SNMM, suggests that elective treatment of the neck should be highly selective in this patient population. Cancer 2018;124:514-20. © 2017 American Cancer Society.