Search

Background/objectives Acral lentiginous melanoma (ALM) is a melanoma subtype associated with atypical locations on the hands and feet and advanced disease at diagnosis. There is a limited understanding of whether the survival is similar for nail, non-nail, lower limb and upper limb ALM patients. We therefore explored clinicopathologic characteristics and melanoma-specific survival of ALM patients according to tumour location. Methods A prospectively collected cohort study was performed of all primary invasive cutaneous acral lentiginous melanomas with known thickness and tumour location reviewed at a tertiary referral centre over 21 years. Results A total of 101 ALM patients were reviewed from 1994 until 2016. The majority of cases (82/101) occurred on the feet. Hand ALMs were thicker and more likely to be ulcerated than feet ALMs (P = 0.05 and 0.02, respectively); however, survival was not statistically different between these two groups (univariate HR 0.48 P = 0.11, 95% CI, 0.20-1.17; multivariate HR 0.67 P = 0.40, 95% CI, 0.27-1.69, respectively). Non-nail ALM patients had longer survival when compared to nail ALM on univariate analysis (HR 0.40, 95% CI, 0.17 to 0.90) which was accounted for by Breslow thickness and ulceration (multivariate HR 0.56, 95% CI, 0.24 to 1.34). Conclusions The reduced melanoma-specific survival in nail ALM patients was likely due to their greater thickness and ulceration. Although hand ALMs are thicker and more frequently ulcerated, this is likely due to the higher proportion of nail ALMs present in this location.

Background/Objectives Scalp melanoma has a worse prognosis than melanoma elsewhere, though the reasons for this are poorly understood. Current literature describing the clinicopathological associations of scalp melanoma is sparse. This study aims to compare clinical and histological features of scalp melanoma with other cutaneous head and neck melanomas (CHNM). Methods A cross-sectional study was performed of all primary CHNM cases seen by the Victorian Melanoma Service between 1994 and 2014, using prospectively recorded clinical data. Invasive and in situ melanomas were compared separately. Results Invasive scalp melanoma was associated with male sex (OR, 2.7; 95% CI, 1.9–3.9), increasing age (OR, 1.02 per year increase in age; 95% CI, 1.01–1.03), being first noticed by a person other than self, spouse/relative or doctor (OR, 2.9; 95% CI, 1.5–5.7), amelanosis (OR, 1.6; 95% CI, 1.1–2.3), and increased growth rate (OR, 1.14 per 1 mm/month growth rate increase; 95% CI, 1.04–1.26). Compared with other CHNM, scalp melanoma had greater median Breslow thickness (2.8 vs 1.2 mm) and was independently associated with satellite metastases (OR, 4.7; 95% CI, 1.9–11.5) and nodular subtype (OR, 1.8; 95% CI, 1.1–3.1). In situ scalp melanoma was associated with male sex, increasing age and solar keratoses. Conclusion Scalp melanoma tends to occur in older men, is often rapidly growing and amelanotic, and is associated with high risk histological features. As it is likely to be overlooked, increased recognition of the atypical presentations of scalp melanoma is required.