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

Primary malignant melanoma of the genitourinary tract: case series of a rare form of primary mucosal melanoma

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 malignant melanoma of the female urethra A rare histopathology case report

Malignant melanoma in the urethra is a rare tumor that is difficult to diagnose and treat, leading to a poor prognosis. In this paper, we present the case of a 36-year-old woman with history of invasive rectal adenocarcinoma (PT2N0Mx) who was tumor free for 5 years presented to urology outpatient with history of poor stream, dysuria, and dyspareuria. On examination, there was a huge mass in the meatus of urethra. Urethral malignant melanoma shows a high rate of local recurrence, about 60 % in 1 year. Overall survival in a series of 11 cases at 3 years was 27 %.

Demographics, Clinical Characteristics and Survival Outcomes of Primary Urinary Tract Malignant Melanoma Patients: A Population-Based Analysis

All primary urinary tract malignant melanoma (ureter vs. bladder vs. urethra) patients were identified from within the Surveillance, Epidemiology, and End Results (SEER) database 2000-2020. Kaplan-Maier plots depicted the overall survival (OS) rates. Univariable and multivariable Cox regression (MCR) models were fitted to test the differences in overall mortality (OM). In the overall cohort (n = 74), the median OS was 22 months. No statistically significant or clinically meaningful differences were recorded according to sex (female vs. male; p = 0.9) and treatment of the primary (endoscopic vs. surgical; p = 0.6). Conversely, clinically meaningful but not statistically significant (p ≥ 0.05) differences were recorded according to the patient's age at diagnosis (≤80 vs. ≥80 years old; p = 0.2), marital status (married 26 vs. unmarried 16 months; p = 0.2), and SEER stage (localized 31 vs. regional 14 months; p = 0.4), and the type of systemic therapy (exposed 31 vs. not exposed 20 months; p = 0.06). Finally, in univariable and MCR analyses, after adjustment for the SEER stage and type of systemic therapy, tumor origin within the bladder was associated with a three-fold higher OM (Hazard ratio: 3.00; p = 0.004), compared to tumor origin within the urethra. In conclusion, primary urinary tract malignant melanoma patients have poor survival. Specifically, tumor origin within the bladder independently predicted a higher OM, even after adjustment for the SEER stage and systemic therapy status.

Primary Malignant Melanoma of the Genitourinary System: A Systemic Review and Report of Eight Cases

Malignant melanoma (MM) of mucosal membranes (excluding anus and head-neck) is a rare but aggressive disease with poor outcomes. The knowledge of this tumor's development, etiology, and management is scarce, mainly due to the low case numbers. We presented eight cases and performed a comprehensive literature review on mucosal MM (between 1970 and 2020). We identified 47 manuscripts on 55 patients with primary mucosal MM (limited to urothelium and vagina) and reviewed demographics, tumor specifications (morphology, stage, etc.), management, and survival. We identified 10 manuscripts discussing treatment in 1595 mucosal and non-mucosal MM and extracted the data regarding the non-surgical treatment modalities of mucosal MM patients. In 63 cases, 48 tumors primarily occurred in the urothelium (urethra: 47, bladder: 1) and 15 in the vagina. Molecular studies in a subset of cases revealed alterations in c-KIT, NRAS, BRAF (non-V600E and V600E), TP53, and NF1. Fifty-three patients underwent surgery (with additional chemotherapy, immunotherapy, and radiotherapy in 19, eight, and eight patients, respectively). The outcome was available in 52 cases, showing 21 deaths, 10 without recurrence, two alive with disease, and five lost to follow-up. Shared genetic signatures in mucosal and skin MM suggest a similar development mechanism; however, unlike skin MM, there are less BRAF mutations and more PI3K/AKT/mTOR pathway alterations in mucosal MM. Prolonged chemotherapy (i.e., methotrexate) and immune-modulating agents (i.e., natalizumab) may be risk factors. The stage at diagnosis and proper surgical extirpation are keys to the prognosis and survival of patients.

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.

Primary malignant melanoma of the urethra in women: About a case

Primary malignant melanoma of the urethra in women is a rare tumor with a poor prognosis. We report the case of a 48-year-old patient who consulted for a mass in the urethral meatus associated with symptoms of the lower urinary tract. The result of the biopsy of the mass revealed a malignant melanoma confirmed by immunohistochemistry. The extension workup was negative. She had a total cystectomy with lymph node dissection done. The one-year follow-up was without particularity.

Primary melanoma of the urinary tract; Clinicopathologic and molecular review of a case series

Primary melanoma of the urinary tract is a very rare and aggressive cancer. It accounts for less than 1% of all the melanoma cases, making it difficult to histopathologically diagnose and manage. We present a retrospective case series of eight primary urinary tract melanoma with clinical, pathological, and molecular findings to add more insight to this challenging disease. These cases were evaluated for histopathological, immunohistochemical, and molecular features of melanoma that were most commonly found in the urethra, followed by those in the bladder and ureter. Identification of nested growth patterns and in situ melanocytic components at cell edges are helpful in the histopathological diagnosis of amelanotic or hypomelanotic tumors. Our results indicate that urinary tract melanoma has several molecular traits, such as gene expression patterns. Genetic mutations may be related to metastasis, as well as provide targets for the management programs.

Primary Urethral Melanoma: A Case Report and Literature Review

Patients with localized urethral melanoma have a high risk of recurrence and poor disease-specific survival. Multi-disciplinary approach including surgery, radiation therapy, and chemotherapy/immunotherapy is needed to maximize survival. Current research efforts include investigation of novel tyrosine kinases as well as the combination of targeted therapies with immunotherapies in this population. Combinations may provide a synergistic effect to overcome various obstacles to disease response.

"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.