ABSTRACT
Primary malignant melanoma of the genitourinary tract is extremely rare. We present two such cases in elderly Caucasian females. An 81-year-old female with urinary retention and polypoid urinary bladder mass and a 72-year-old female with gross hematuria and urethral caruncle. After thorough evaluation, they were both eventually diagnosed with primary urogenital melanoma (SOX10 and MART1-positive in tumor cells). In both cases, the presence of melanoma-in-situ and absence of primary melanoma in other sites were consistent with primary urogenital melanoma. Immunotherapy with PD-1 inhibitors and use of neoadjuvant and adjuvant treatment are promising, as treatment guidelines remain unclear and overall survival is low. Additional clinical reporting of primary urogenital melanomas can help in better understanding and ultimately treating it.
Primary melanomas of the bladder and urinary tract are rare and usually deadly. They represent only 0.2% of all melanomas, including melanomas of skin. They can be difficult to diagnose and treat due to how rare they are and the lack of clear treatment guidelines. We present two cases of elderly Caucasian women who were unexpectedly diagnosed with primary melanoma cancers of the bladder and urinary tract after having surgery and analyzing tissue that was removed. Both tissue samples had features specific to melanoma and there was no cancer in any other organ, thus making them primary melanomas of the bladder and urinary tract. Current treatment approaches with surgery and chemotherapy have not improved the survival outcomes and prognosis associated with this disease, but treatment before and after surgery as well as cancer treatments that harness the person's own immune system are promising. By reporting additional clinical experiences of this often fatal disease, we hope it can be better understood and appropriately managed in the future.
