Sinonasal Mucosal Melanoma: A Population-based Comparison of the EUROCARE and SEER Registries.

 Sinonasal melanomas are rare tumors with no comparative survival studies between Europe and the US.  To provide a population-based survival analysis between the two continents.  The European Cancer Registry (EUROCARE) and the United States Surveillance, Epidemiology, and End Results (SEER) databases were queried to identify patients diagnosed with sinonasal melanoma between 2000 and 2007. Relative survival (RS) data were grouped by age, gender, geographic region, extent of disease, and treatment modality.  A total of 1,294 cases were identified between 2000 and 2007 (935 from EUROCARE-5 and 359 from SEER). Females were most commonly identified in Europe (56.4%) and in the US (54.9%). Patients over the age of 65 years comprised the greatest proportion of patients in Europe (70%) and in the US (71%). By region, Southern Europe had the highest 5-year RS (31.6%, 95% confidence interval [CI] = [21.3-42.5%]), and Eastern Europe the lowest (16.5%, [7.5-28.5%]). The aggregate European 5-year RS was 25.4% [21.8-29.1%] and the U.S. was (29.7%, [23.6-36%]).  Although increasing in incidence, sinonasal melanomas remain rare. Women were more commonly affected. The most common age group was those older than 65 years, although age did not confer a prognostic value. The most common subsite was the nasal cavity followed by the maxillary sinus. Five-year RS was similar between continents with an inverse relationship between extent of disease and survival. The treatment of choice throughout Europe and the US remains primarily surgical.