Baseline Serum Neutrophil-to-Lymphocyte Ratio in Acral Melanoma Compared to Non-Acral Melanoma and its Prognostic Significance

BACKGROUND:Acral lentiginous melanoma (ALM), a cutaneous melanoma subtype, exhibits a poorer prognosis than non-acral cutaneous melanoma (NACM). The neutrophil-to-lymphocyte ratio (NLR) is emerging as a prognostic indicator across diverse cancers. OBJECTIVE:We explored the baseline NLR disparities between ALM and NACM, and the NLR's prognostic significance in patients with ALM. METHODS:We reviewed records of patients with ALM and NACM diagnosed between 1997 and 2022, analyzing medical data. RESULTS:Among 327 and 159 patients with ALM and NACM, respectively, baseline NLR varied based on distinct clinicopathological factors between ALM and NACM. In stage 3-4 melanomas, the median NLR for ALM (2.18; interquartile range, 1.70-3.08) significantly surpassed NACM (1.74; interquartile range, 1.33-2.53) (P=0.029). In patients with ALM, high NLR (hazard ratio, 1.64; 95% confidence interval, 1.02-2.66; P=0.043) was independently correlated with poor progression-free survival when adjusting for ulceration, Breslow thickness ≥2 mm, and nodal invasion. LIMITATIONS:Single-center, retrospective design. CONCLUSION:Advanced-stage ALM exhibited a significantly higher baseline NLR compared to that of NACM. Evaluating baseline NLR could provide valuable prognostic insights for patients with ALM.