Melanoma of the female urethra

[Primary melanoma of female urethra: A case diagnosed in Ouagadougou]

We report a case of primary melanoma of a female urethra diagnosed at a non-metastatic stage in a 48-year-old patient with a history of breast carcinoma treated with radiotherapy and hormone therapy. The patient was consulting for dysuria, hematuria, and perineal pain. The clinical examination found a prolapsed and black mass, developed at the expense of the urethra and located at the anterosuperior part of the vulva. The mass biopsy revealed a proliferation of fusiform and globular cells loaded with black pigment expressing the anti-HMB 45 and PS 100 antibodies. The extension assessment showed an absence of secondary localization. The patient underwent total cystourethrectomy without inguinal lymphadenectomy. There was no recurrence observed on day 100 following the surgery.

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 male urethra: Case report and review of literature

INTRODUCTION

We report a rare case of primary malignant melanoma with inguinal lymph node metastasis in the male urethra.

CASE PRESENTATION

A 57-year-old male patient presented with a small tumor on the ventral surface of the penis, which was discovered 5 months ago and did not cause pain or discomfort. In the past month, the patient has developed symptoms of urinary incontinence. MRI and PET/CT scans revealed a primary tumor in the penile urethra, but no metastases were found. The patient underwent partial penectomy surgery and laparoscopic bilateral inguinal lymphadenectomy within one month. The pathological combined with immunohistochemical staining confirmed primary malignant melanoma in the urethra with right inguinal lymph node metastasis. Despite complying with surgical and immunotherapy treatment with Pembrolizumab for 18 cycles, the patient was diagnosed with recurrent cancer in the penile stump after 05 months and he passed away after 18 months.

DISCUSSION

Urethral melanoma is a rare and highly invasive type of cancer. It was often diagnosed at a late stage because the initial symptoms were not obvious in the lower urinary tract. Additionally, cancer progressed very quickly, making it difficult to treat.

CONCLUSION

Urethral melanoma, if detected at a late stage with lymph node metastasis, has a significantly poor prognosis irrespective of the treatment method employed. However, to our best knowledge, very few publications can be found on this disease, and the strategic treatment remained unknown.

Urethral Melanoma – Clinical, Pathological and Molecular Characteristics

BACKGROUND:

Mucosal melanoma involving the urethra is a rare disease with distinct clinical and molecular characteristics and poor outcomes. Our current knowledge is limited by the small number of reports regarding this disease.

OBJECTIVE:

To describe the clinical, pathological, and molecular characteristics of urethral melanoma.

METHODS:

We summarized the clinicopathologic data for 31 patients treated for urethral melanoma from 1986–2017 at our institution. Genomic data from our institutional sequencing platform MSK-IMPACT (n = 5) and gene-specific PCR data on BRAF, KIT, and/or NRAS (n = 8) were compared to genomic data of cutaneous melanomas (n = 143), vulvar/vaginal melanomas (n = 24), and primary non-melanoma urethral tumors (n = 5) from our institutional database.

RESULTS:

Twenty-three patients were diagnosed with localized disease, 7 had regional/nodal involvement and one had metastases. Initial treatment included surgery in 25 patients; seven had multimodal treatment. Median follow-up was 46 months (IQR 33–123). Estimated 5-year cancer-specific survival was 45%. No significant change in survival was observed based on a year of treatment.

Primary urethral melanomas showed a higher frequency of TP53 mutations compared to cutaneous (80.0% vs. 18.2%, p = 0.006) and vulvar/vaginal melanomas (80.0 vs. 25.0%, p = 0.04). BRAF mutations were absent in urethral primaries (0% vs. 46% in cutaneous melanoma, p = 0.02). Tumor mutation burden was higher in cutaneous than urethral melanomas (p = 0.04). Urethral melanomas had a higher number of somatic alterations compared to non-melanoma urethral tumors (median 11 vs. 5, p = 0.03).

CONCLUSIONS:

Our findings support a unique mutational landscape of urethral melanoma compared to cutaneous melanoma. Survival remains poor and is unchanged over the time studied.

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 urethral melanoma treated sucessfully with wide excision and combination immunotherapy: Case report and review of literature

We report the rare case of a primary malignant melanoma of the urethra. An 89-year-old African American woman who was referred to our urology clinic for intermittent gross hematuria and a palpable vaginal mass of two months duration. Cystoscopy revealed a 3 cm mass in the distal urethra and urethral meatus that was surgically resected by wide local excision. The histopathologic diagnosis was primary malignant melanoma of the urethra. The patient was subsequently treated with adjuvant EBRT and immunotherapy with nivolumab and ipilimumab. Post-treatment PET-CT showed good response to treatment and patient remained in remission at eight month follow up.

Urethral Masses

Urethral and periurethral masses in women include both benign and malignant entities that can be difficult to clinically differentiate. Primary urethral carcinoma is rare and the optimal treatment modality may vary depending on the stage at presentation. Because cancer-free survival is poor, clinicians shouldhave a high index of suspicion when evaluating a urethral mass. Some benign-appearing urethral masses may be safely observed. Surgical resection is an effective option that should be used based on patient preference and symptoms, and for suspicious lesions.

Primary urethral small cell melanoma with neuroendocrine differentiation: a case report

BACKGROUND

Primary malignant melanoma of the female urethra is an exceedingly rare tumor. It represents 0.2% of all malignant melanomas. Divergent differentiation towards non-melanocytic lineages has not been reported in urethral melanoma.

CASE PRESENTATION

We report a rare case of neuroendocrine differentiation in a large primary small cell malignant melanoma involving the urethra, in a 62-year-old lady, who presented with obstructive urinary symptoms. Clinical and radiological workup revealed a large urethral mass with liver and lymph nodal metastases. A biopsy was performed from the urethral and liver lesions which showed poorly differentiated tumor cells with small cell morphology and presence of melanin pigment. These cells were immunopositive for melanocytic and neuroendocrine markers. Ultrastructural examination showed presence of melanosomes and neurosecretory granules in the tumor cells.

CONCLUSIONS

Although malignant melanoma with neuroendocrine differentiation is exceptionally rare, it needs to be recognized among the other well-known variants of malignant melanoma.

[PRIMARY MALIGNANT MELANOMA OF THE FEMALE URETHRA: A CASE REPORT]

We report a case of primary malignant melanoma (MM) of the female urethra. A 60-year-old female complained bleeding from the urethral meatus. MRI revealed a mass of 20 mm at the external urethral meatus. Pathological examination of transurethrally resected specimens revealed MM with stromal invasion. She underwent total urethrectomy plus cystostomy and sentinel lymph node biopsy. The tumor was pathologically confined in the specimen and no lymph node metastasis was found. She received interferone β as adjuvant therapy. However, she developed bilateral adrenal and pulmonary hilar lymph node metastases 1 year after urethrectomy. Although she started to receive nivolumab as salvage therapy, the disease progressed as well as development of interstitial pneumonia (IP) after four cycles. Following improvement of IP with steroid therapy, she started to receive ipilimumab, which resulted in the development of intolerable IP of grade 3. The patient finally died of MM 19 months after the initiation of treatment.

Melanoma of the glans penis and urethra

Primary melanoma of the glans or male urethra is a rare malignant tumor with high mortality. We searched PubMed and found 129 articles reporting on 220 patients. All articles were case reports or case series. Median patient age was 65 years. Median survival was 28 months, with 5-year survival in approximately 10%. All patients who survived over 5 years had a localized disease (stage I/A) with invasion depth <3-3.5 mm. Wide local excision with sentinel lymph node biopsy is the treatment of choice for patients with localized disease. For advanced disease, the prognosis is poor.