Primary Malignant Melanoma of the Bladder: A Rare Case Report

Abstract

Background
Primary malignant melanoma (PMM) of the bladder is a rare ailment and has a poor prognosis; only 40 cases of PMM reported in literature till date. In this case report we described a case of PMM of the bladder, treatment, and a review of the literature as the recommended treatment choices are not widely known.
Case Presentation
A 55-year-old Indian female came with a history of hematuria for two-months. Ultrasonography revealed a 18×16 mm size mass located in the antero-inferior wall of urinary bladder with involvement of bladder neck. She underwent transurethral resection of the bladder tumor outside and histologically reported to be malignant melanoma and confirmed on immunohistochemistry (IHC). No further primary sites of melanoma were found. Computed tomography (CT) showed an irregular enhancing mucosal thickening along internal urethral meatus and adjacent urinary bladder. The patient eventually underwent radical cystectomy with anterior pelvic exenteration with ileal conduit.

Conclusion
Primary bladder melanoma is very aggressive in nature. In most of the cases bladder malignant melanoma is secondary, so extensive search for any primary melanotic lesion is essential. It is often difficult to discriminate whether a bladder melanoma is primary or metastatic. Certain diagnostic features can be obtained through histopathological investigation, immuno-histochemistry, clinical history, and endoscopic evaluation. Despite a wide range of treatments, people with PMM still have a worst prognosis.