Nodal and distant metastases in sinonasal mucosal melanoma: A population-based analysis

Objectives/Hypothesis Sinonasal mucosal melanoma (SNMM) is a rare malignant neoplasm. No study to date has analyzed the impact that nodal metastases and distant metastases at diagnosis have on overall survival (OS) and disease-specific survival (DSS). Study Design Retrospective database review. Methods The Surveillance, Epidemiology, and End Results database was queried for cases of SNMM. Descriptive statistics were used analyze patient demographic and clinicopathologic variables. The Kaplan-Meier model was used to analyze survival, and the Cox proportional hazards model was used for multivariate analysis. Results Three hundred twenty-eight cases of SNMM were identified. The most frequent sinonasal anatomic location was the nasal cavity in 279 (73.0%) patients, followed by the maxillary sinus in 60 (15.7%) patients. Regional nodal metastases at diagnosis occurred in 33 (8.6%) patients, whereas distant metastases at diagnosis occurred in 41 (10.7%) patients. Five-year OS was 22.7%, and 5-year DSS was 26.8%. The presence of positive nodes at diagnosis (OS P < .0001, DSS P < .0001), distant metastases at diagnosis (OS P = .0442, DSS P = .0442), primary tumor site (OS P < .0001, DSS P < .0001), and increasing age (OS P = .0012, DSS P = .0016) were found to be significant as negative predictors of OS and DSS. Conclusions SNMM is a rare pathologic entity with a poor prognosis. The presence of nodal and distant metastases at diagnosis are negative prognostic factors in OS and DSS. These factors can be used in the development of new models of risk stratification and to inform treatment strategies and surveillance patterns. Level of Evidence NA Laryngoscope, 130:622-627, 2020