Desmoplastic Melanoma: Clinical Characteristics and Survival in the US Population.

Objective Desmoplastic melanoma (DM) is a rare variant of invasive malignancy of the skin pigmented cells. We present a comprehensive study reporting on US demographics, disease characteristics, and survival, to contribute to the current knowledge and raise awareness of this rare disease. Materials and methods The demographics of DM patients diagnosed from January 1, 2004, to December 31, 2015, were obtained by querying the National Cancer Database. The characteristics of DM were compared with common malignant melanoma (CMM) using univariate and multivariate regression models. Five-year overall survival (OS) curves were estimated using Kaplan-Meier analyses and the Cox proportional regression model. Results Our query found 5,895 patients diagnosed with DM and 292,939 patients with CMM. DM tended to present at an older age, a more advanced stage, and with a Breslow depth greater than 4 mm at diagnosis (P<.05). The Kaplan-Meier survival analysis demonstrated a five-year OS for DM and CMM of 75% and 76%, respectively, without any statistical difference (P=.07). Cox regression analysis demonstrated that age at diagnosis and comorbidities were independent predictors of five-year OS for DM (P<.001). Conclusions Older age, advanced stage, and higher Breslow depth were found to be independent positive factors associated with DM.