The role of wide local excision of a primary lesion in cutaneous malignant melanoma: a retrospective analysis of its usefulness in local and general control of disease.

Currently, wide local excision is recommended after the primary excision of cutaneous melanomas. The definition of margins for wide local excision indicated by the guidelines has remained unchanged over the years, although the reported indications are derived from fairly dated studies in which melanomas tended to be thicker or in advanced stages at diagnosis. This study aimed to retrospectively evaluate the usefulness of wide local excision for local and general control of the disease and to identify patients who had benefited from the wide local excision procedure in terms of prognosis improvement. This retrospective observational study was conducted on patients who had undergone surgery for melanoma at a single institution. The primary endpoint was progression-free survival after wide local excision in patients with or without residual melanoma. The secondary endpoint was to evaluate which patients' demographic features and melanoma histological data were associated with residual melanoma after wide local excision. In the univariate model, melanoma-positive wide local excision resulted in the worst progression-free survival; however, this association was not confirmed in the multivariate model. The results also showed that Breslow thickness was the only factor associated with an increased risk of metastasis to the wide local excision area. According to the receiver operating characteristic analysis, the optimum cutoff value of Breslow's thickness to predict a tumor-positive wide local excision was 2.31 mm for males and 2.4 mm for females.