Abstract
Malignant melanoma (melanoma) is a tumor of melanocytes that usually presents as cutaneous lesions. While melanoma can infrequently appear as a primary tumor elsewhere in the body, it is extremely rare in the urethra and even rarer as amelanotic malignant melanoma. We report the case of a 66-year-old male who presented with painless gross hematuria and lower urinary tract obstructive symptoms in the recent 2 weeks prior to his visit to our clinic. History and physical examination, including external genital examination, abdominopelvic sonography, and urine culture, were not conclusive. Cystourethroscopy revealed a creamy pink fragile mass located in the anterior proximal urethra that extended to the mid portion. Pathological examination of this lesion confirmed the diagnosis of amelanotic malignant melanoma using immunohistochemistry. Radical cystourethrectomy with ileal conduit was subsequently conducted. Although this tumor is extremely rare, urologists and pathologists should consider malignant melanoma as a diagnosis in patients with urethral tumor because of the likelihood of early metastasis and, consequently, poor prognosis. Complete surgical removal of the tumor and use of effective therapies can improve outcomes in these patients.
Highlights
Known as melanoma, is a neoplasm of pigment-producing cells known as melanocytes
A 66-year-old male was referred to our clinic; the patient complained of painless gross hematuria and severe lower urinary tract obstructive symptoms in the recent 2 weeks prior to his visit
Considering the rarity of urethral malignant melanomas, especially the amelanotic variant, we examined the patient thoroughly and found no other lesion
Summary
Known as melanoma, is a neoplasm of pigment-producing cells known as melanocytes. Melanoma of the urethra is an extremely rare tumor, amelanotic melanoma is an even rarer entity.[1,2] Early diagnosis and use of effective therapies after tumor removal can remarkably improve patient outcomes. Transurethral biopsy of the mass lesion was conducted, and the specimen was sent to the pathology laboratory (Figure 1). Considering the rarity of urethral malignant melanomas, especially the amelanotic variant, we examined the patient thoroughly and found no other lesion. We confirmed the diagnosis of primary melanoma of the urethra. The patient progressed to metastatic lesions despite receiving standard systemic treatment and expired due to progressive disease 18 months later. The histological image suggested possible malignant tumors, including malignant melanoma and urothelial carcinoma (Figure 2). Immunohistochemistry (IHC) confirmed the diagnosis of malignant melanoma (Figure 3)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
