Regression and Sentinel Lymph Node Status in Melanoma Progression.

BACKGROUND The purpose of this study was to assess the role of regression and other clinical and histological features for the prognosis and the progression of cutaneous melanoma. MATERIAL AND METHODS Between 2005 and 2016, 403 patients with melanoma were treated and followed at our Department of Dermatology. Of the 403 patients, 173 patients had cutaneous melanoma and underwent sentinel lymph node (SLN) biopsy and thus were included in this study. RESULTS Histological regression was found in 37 cases of melanoma (21.3%). It was significantly associated with marked and moderate tumor-infiltrating lymphocyte (TIL) and with negative SLN. Progression of the disease occurred in 42 patients (24.2%). On multivariate analysis, we found that a positive lymph node and a Breslow index higher than 2 mm were independent variables associated with disease free survival (DFS). These variables together with a mild TIL were significantly correlated with overall survival (OS). The presence of regression was not associated with DFS or OS. CONCLUSIONS We could not demonstrate an association between regression and the outcome of patients with cutaneous melanoma. Tumor thickness greater than 2 mm and a positive SLN were associated with recurrence. Survival was influenced by a Breslow thickness >2 mm, the presence of a mild TIL and a positive SLN status.