Lentigo maligna melanoma excised with histological margins of 3mm or less have increased risk of relapse

July 18, 2023

Abstract

Background: Most surgical margins for lentigo maligna melanomas reported in the literature are clinical and not histologic.

Objective: We sought to determine whether histologic margin status is an independent predictor of progression.

Methods: Clinicopathologic information of 268 invasive lentigo maligna melanomas diagnosed from 1990 to 2019 were analyzed. Statistical analyses were performed using Cox proportional-hazards model and Boruta method.

Results: 75% of the lesions were located on the head and neck. The range of follow-up for all patients is 0 to 31.8 years (median, 10.2 years). Time to local recurrence ranges from 0 to 20 years (median, 3 years). Progression developed in 54/268 (20.1%) patients. Local recurrence only was seen in 36/268 (13.4%), both local recurrence and subsequent metastasis in 7/268 (2.6%), and only metastasis in 11/268 (4.1%) patients. Histologic margin status (positive and close/less than 3 mm) and tumor site (head and neck location) significantly correlated with worse progression-free survival.

Limitations: Single institution and retrospective study.

Conclusions: Histologic margin status is the strongest predictor of progression for lentigo maligna melanoma. Patients with positive or close/less than 3mm histological margins should consider a re-excision due to the increased risk of relapse.

Reference:

Mai P. Hoang, Pawel Karpinski, Miguel Zúñiga-Castillo, Ruth K. Foreman, Kevin S. Emerick, Arthur J. Sober, Histologic Margin Status is a Predictor of Relapse in Lentigo Maligna Melanoma, Journal of the American Academy of Dermatology, 2023, ISSN 0190-9622,
https://doi.org/10.1016/j.jaad.2023.07.008.