The prognostic impact of the extent of ulceration in clinical stage I-II melanoma patients: A multicenter study of the Italian Melanoma Intergroup (IMI).
The presence of ulceration has been recognized as an adverse prognostic factor in primary cutaneous melanoma (PCM).To investigate whether the extent of ulceration (EU) predicts relapse free survival (RFS) and overall survival (OS) in PCM.477 patients with ulcerated PCM were retrieved from databases of Italian Melanoma Intergroup. Univariate and multivariable Cox proportional hazard models were used to assess the independent prognostic impact of EU.A significant interaction emerged between Breslow thickness (BT) and EU considering both RFS (p<0.0001) and OS (p=0.0006). At multivariable analysis, a significant negative impact of EU on RFS (HR [1 mm increase] 1.26, 95%CI 1.08-1.48, p=0.0047) and OS (HR [1 mm increase] 1.25, 95%CI 1.05-1.48, p=0.0120) was found in patients with BT ≤2 mm, after adjusting for BT, age, tumor-infiltrating lymphocytes, sentinel lymphnode status and mitotic rate. No impact of EU was found in patients with 2.01-4 mm and >4 mm BT.This study demonstrated that EU has an independent prognostic impact in PCM and should be recorded as a required element in pathology reports.