Female urethral malignant melanoma with vesical invasion: a case report

Exploring the landscape of urinary tract melanomas: A review for pathologists and clinicians

Melanomas originating within the urinary tract represent a rare and clinically challenging subset of malignancies. Despite extensive research on cutaneous melanomas, urinary tract melanomas remain relatively unexplored, presenting diagnostic dilemmas and limited treatment consensus. In this comprehensive review, we synthesize current knowledge on the epidemiology, risk factors, clinical presentation, histopathological characteristics, and treatment strategies specific to this disease. Enhancing clinical awareness, refining diagnostic approaches, and exploring novel therapeutic interventions hold promise for improving outcomes in this challenging malignancy subset.

А rare case of primary malignant melanoma of the female urethra

Primary malignant melanoma of the female urethra is an extremely rare disease. Its frequency is only 0.2% of all malignant melanomas. This type of carcinoma is associated with a poor prognosis and short survival due to the early occurrence of metastases and delayed diagnosis. We present a patient with primary malignant melanoma invading the distal urethra, part of the labia minora, and sections of the anterior vaginal wall, where 15 months of overall survival were achieved against the background of the complex treatment.

Identification of distinct genomic features reveals frequent somatic AHNAK and PTEN mutations predominantly in primary malignant melanoma presenting in the ureter

BACKGROUND

Primary malignant melanoma of the ureter is extremely rare. Genetic variants to the increased risk of developing the disease have not yet been investigated.

METHODS

Tumour mutation profiling for primary malignant melanoma of the ureter was performed by whole-exome sequencing. Immunohistochemistry was performed to verify histopathological features and the variants of predisposing genes and driver mutation genes. Furthermore, we conducted a literature review and Surveillance, Epidemiology and End Result-based study by searching public databases.

RESULTS

We identified 38 somatic single nucleotide variants and 9 somatic insertions and deletions (INDELs) in tumour specimens. After filtering with the Cancer Gene Census database, seven predisposing genes and two driver mutation genes were identified. Moreover, the immunohistochemical profile showed that tumour cells were positive for Melan-A, melanoma gp100 human melanoma black 45 (HMB45), S100 beta and P53. The expression levels of two driver mutation genes (phosphatase and tensin homolog (PTEN) and desmoyokin (AHNAK) and five predisposing genes (AT-rich interaction domain 1B (ARID1B), catalase, eukaryotic translation initiation factor 4 gamma 3 (EIF4G3), ANK3 and collagen type I) were significantly downregulated in tumour tissues compared to paracancerous tissues. In the literature review and Surveillance, Epidemiology and End Results-based study, patients with primary malignant melanoma of the urinary tract had worse clinical outcomes than patients with primary urothelial carcinoma after 1:2 propensity score matching (P = 0.010). Additionally, Cox multivariate analysis for patients with primary malignant melanoma of the urinary tract indicated that distant metastasis (hazard ratio = 1.185; P = 0.044) was an independent predictor for overall survival, and tumour focality (hazard ratio = 0.602; P = 0.017) and non-surgery (hazard ratio = 0.434; P = 0.003) were independent factors for tumour progression.

CONCLUSIONS

Our study is the first to provide evidence that the distinct phenotypes of primary malignant melanoma of the ureter may be due to different genetic variations. The prognosis of primary malignant melanoma of the urinary tract was poorer than that of primary urothelial carcinoma of the urinary tract.

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.

Primary amelanotic melanoma of the male urethra: A rare entity and diagnostic challenge

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.

"Man in Istanbul" Lesions of the Urinary Tract (Known Entities in an Unusual Context): Melanoma, Carcinoid Tumors, Epithelioid Angiosarcoma

Certain tumors are more difficult to recognize when they present in an unusual location. Within the urinary tract, primary melanomas, carcinoid tumors, or epithelioid angiosarcoma could present diagnostic challenges due to their infrequent occurrence. This article emphasizes the clinical and histopathologic features of these entities and their differential diagnoses including the immunophenotype and their prognoses.

Primary malignant melanoma of the female urethra: Report of a rare neoplasm of the urinary tract

INTRODUCTION

Melanoma is a malignant tumor that can affect any area of the anatomical economy. Its occurance in the female urethra is extremely rare. We report a case of primary malignant urethral melanoma developed in an elderly female patient.

PRESENTATION OF CASE

A 70 years old female presented with dysuria, poor stream, gross haematuria, intermittent blood spots, and a painful mass. On physical examination, there were no suspicious lesions on the skin. On external genital examination, a lesion at the level of the urethral meatus was observed. The mass was removed by wide local excision under spinal anaesthesia. The pathological diagnosis was malignant melanoma of the urethra.

DISCUSSION

The common presentations include bleeding and/or discharge per urethra, voiding dysfunction and the presence of tumor mass. Survival depends on the stage, location and size of the neoplasm at the time of diagnosis. Despite major surgery, radiotherapy or immunotherapy; malignant melanoma usually has a poor prognosis.

CONCLUSION

Melanoma of the female urethra is an extremely uncommon pathology leading to paucity of literature and any definite recommendations regarding management. The histological and immunohistochemical findings can be helpful in making an early and accurate diagnosis of malignant melanoma in the urogenital region.

Primary malignant melanoma of the female urethra

We report here on a rare case of primary malignant melanoma of the female urethra. A 69-year-old female presented at our hospital with a several month history of dysuria, poor stream, gross hematuria, intermittent blood spots, and a painful mass at the external urethral meatus. The physical examination revealed a soft, small, chestnut-sized lesion through the urethral orifice. The mass was tan colored, ulcerated, covered with necrotic tissue, and protruded from the external urethral meatus. The mass was removed by wide local excision under spinal anesthesia. The pathological diagnosis was malignant melanoma of the urethra. Computed tomography of the abdomen as well as a whole-body bone scan showed no evidence of metastasis. The patient has been free of disease for 6 months postoperatively. We discuss the clinicopathologic features and treatment of this tumor.