A rare case of primary bladder malignant melanoma: a case report

Primary melanoma of the bladder is an extremely rare malignant tumor. In recent years, only a few sporadic cases have been reported. We report a 59-year-old male patient who presented with gross hematuria and had bladder irritation symptoms such as frequent urination, urgency, and pain. CT imaging showed multiple exophytic small nodules on both sides of the bladder; under cystoscopy, multiple coral-like neoplasms were visible on both sides of the bladder, with no obvious bleeding on the surface, and the largest one was approximately 1.5 cm × 1.2 cm. No evidence of primary melanoma in other parts was found during the comprehensive examination. After the patient underwent transurethral resection of bladder tumor, he received regular intravesical instillation of epirubicin hydrochloride treatment. No recurrence was observed during the 5-month follow-up period. There were no more than 50 cases of primary bladder melanoma reported globally. Further immunohistochemistry should be performed as far as we know, this case is the first report of primary bladder malignant melanoma in Bijie City, Guizhou Province. The prognosis of this disease is generally poor, and its clinical diagnosis is relatively difficult. Immunohistochemistry plays a crucial role in its diagnosis. Due to insufficient understanding of it, there is currently no unified treatment standard.