Prognostic value of ulceration varies across Breslow thicknesses and clinical stages in acral melanoma: a retrospective study

Background Ulceration is regarded as an adverse prognostic factor and is used together with tumour thickness to subcategorize patients with cutaneous melanoma. However, the prognostic impact of ulceration in acral melanoma (AM) is controversial. Objectives To assess the prognostic impact of ulceration in AM and the variability across different Breslow thicknesses and clinical stages. Methods A multicentre retrospective study of patients diagnosed with AM between January 2000 and December 2017. Differences in melanoma-specific survival (MSS) between patients with and without ulceration were assessed using the multivariable Cox proportional hazards model and log-rank test. Results Among 1053 enrolled patients, 62.6% had ulceration. After a median follow-up of 61 months, patients with ulceration had a lower median MSS than those without: 66.1 months, 95% confidence interval (CI) 60.0-86.0 vs. not reached; hazard ratio 1.41, 95% CI 1.09-1.82; P = 0.012. Among patients with thin (<= 1 mm) melanoma, the survival curves of patients with vs. without ulceration clearly separated over time (P < 0.001). No association between ulceration and MSS was observed for melanomas of thickness > 1 mm (subgroups of T2, T3 and T4; all P-values > 0.05) or patients with stage III disease (hazard ratio 1.09, 95% CI 0.71-1.68, P = 0.39). Conclusions Ulceration is an independent negative prognostic factor for patients with AM, but the impact varies across Breslow thicknesses and clinical stages. Ulceration has a significant effect on prognosis for patients with thin (<= 1 mm) melanoma, but there was no association between ulceration and survival in intermediate/thick AM or stage III AM.

Automated summary

This study assessed the prognostic impact of ulceration in acral melanoma (AM) and found that ulceration is an independent negative prognostic factor for AM patients, but the impact varies across different Breslow thicknesses and clinical stages.