Acral Lentiginous Melanoma: A Clinicoprognostic Study of 149 Cases at a Single Institution

Abstract

Objective The objective of this study is to investigate the epidemiological features, clinical characteristics, and pathological characteristics of acral lentiginous melanoma (ALM) and identify prognostic factors. Methods A total of 149 patients diagnosed with ALM between August 2008 and December 2019 at the National Cancer Center (NCC) of China were retrospectively analyzed. Follow-up data on patient survival status were collected. Survival curves were generated using the Kaplan-Meier method, and statistical significance was assessed using the log-rank test. Additionally, a Cox proportional hazards model was constructed to identify prognostic factors. Results All patients included in this study were of Chinese ethnicity, with an average age of 52.4 ± 14.8 years (range, 15-80 years) at the time of diagnosis. No gender predilection or genetic susceptibility was observed. The plantar region was the most frequently affected site among primary lesions. Notably, only 17 (11.4%) patients reported a history of trauma. Statistical analysis revealed that a lesion duration of ≤2.5 years, Breslow thickness >4.0 mm, high mitotic rate (>6 mm−2), presence of vascular invasion, and regional lymph node metastasis were identified as independent prognostic factors. Conclusion Our findings indicate that a lesion duration of ≤2.5 years, Breslow thickness >4.0 mm, high mitotic rate (>6 mm−2), presence of vascular invasion, and regional lymph node metastasis are significantly associated with a poorer prognosis for patients with ALM.