In primary melanomas, we found a strong association between higher MC1R expression and a Breslow’s depth greater than 1 mm (p < 0.0001), presence of ulceration (p = 0.0008), presence of BRAFV600E mutation (p = 0.008), and mucosal melanoma versus non-mucosal melanoma (p = 0.0279) (Table 1). Here, MC1R is linked to mucositis.