Urological Melanoma: A Comprehensive Review of a Rare Subclass of Mucosal Melanoma with Emphasis on Differential Diagnosis and Therapeutic Approaches

Melanoma is reported as the 19th most common cancer worldwide, with estimated age-standardized incidence rates of 2.8–3.1 per 100,000. Although the origin is most frequently cutaneous, mucosal melanoma has been described several times in literature, and despite its rarity (only 1% of all melanomas), increasing attention is being paid to this disease form. Within this subgroup, melanomas of the uropoetic apparatus are a rarity among rarities. Indeed, less than 50 cases of primary melanoma originating from the urinary bladder have been described, and even less originating from the kidney, renal pelvis and urethra. In this work, we present a detailed review of the literature related to this subclass of mucosal melanoma, delve into the biological landscape of this neoplasm and discuss current approaches, future perspectives and potential therapeutic approaches.