Malignant melanomas of female urethra

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.

[Case of primary amelanotic malignant melanoma of the female urethra]

We report a rare case of primary amelanotic malignant melanoma of the female urethra. A 58-year-old female with complaint of nodule on the external urethral meatus was referred to our hospital. Pathological diagnosis of the biopsy specimen from the nodule was malignant melanoma. Computed tomography of the chest and abdomen as well as bone scan showed no evidence of metastasis. Sentinel biopsy from the inguinal lymph nodes revealed no metastasis. Thereafter, the patient underwent radical urethrectomy, whose limits of resection were the bulbocavernosal muscles bilaterally, the arch of the pubic symphysis anteriorly, the anterior vaginal wall posteriorly, and the urethra up to the level of the bladder neck superiorly. The histopathological diagnosis was amelanotic malignant melanoma of the urethra. The patient had received six cycles of DAV-Feron (dacarbazine, nimustine, vincristine, and interferon-beta) in an adjuvant setting, and there is no sign of recurrence 25 months after operation.

Unexpected Long Survival in Primary Malignant Melanoma of the Male Urethra

A case of primary malignant melanoma of the urethra in a 60-year-old male is presented. Despite multiple adverse prognostic factors and against expectations, after a follow-up of 5.5 years he is still alive.

Primary amelanotic malignant melanoma of the female urethra

The case is reported of amelanotic malignant melanoma of the female urethra mimicking urethral caruncle. A 75-year-old woman complained of a mass of the external meatus. Urethral carunclectomy was performed, but histological diagnosis was amelanotic malignant melanoma. Finally, she underwent en block resection of urethra including bladder neck, uterus, adnexa, vagina, and vulva. As urinary diversion, she underwent a continent cathererizable stoma with an appendicovesicostomy, according to the method described by Mitrofanoff, and Y-V graft for reconstruction of the vulva.

Primary malignant melanoma of the urethra: a clinicopathologic analysis of 15 cases

The clinical and pathologic features of 15 primary urethral melanomas occurring in patients (nine women and six men) age 44 to 96 years (mean age, 73 yrs) are described. In the men the tumor involved the distal urethra. In eight women it involved the distal urethra, usually the meatus; both the distal and proximal urethra were involved in one woman. The tumors were typically polypoid and ranged from 0.8 to 6 cm (mean, 2.6 cm) in maximum dimension. A vertical growth phase was present in all tumors, with a prominent nodular component in seven of them. A radial growth phase was seen in nine tumors. The depth of invasion ranged from 2 to 17 mm. The tumors had diffuse, nested, storiform, or mixed growth patterns. The neoplastic cells typically had abundant eosinophilic cytoplasm, large nuclei with prominent nucleoli, and brisk mitotic activity. Melanin pigment was seen in 12 tumors but was conspicuous in only six. At the time of diagnosis, 13 tumors were confined to the urethra and two patients had lymph node metastasis. Nine patients died of disease 13 to 56 months after initial diagnosis and treatment, and one patient had a local recurrence at 4 years and subsequently died of sepsis 1 year later. Three patients were alive and well at 11 months, 23 months, and 7 years. One patient died at the time of the initial operation, and one died of a ruptured aortic aneurysm at 3 years without evidence of melanoma at autopsy. Primary malignant melanomas of the urethra, one fifth of which are amelanotic, must be included in the differential diagnosis of a number of primary neoplasms that involve the urethra, including transitional cell carcinoma, sarcomatoid carcinoma, and sarcomas. Conventional prognostic factors, such as depth of invasion or tumor stage, do not seem to play as important a role in predicting survival as the mucosal location and the nodular growth present frequently in these tumors.

Primary malignant melanoma of the female urethra: a case report

A case of primary malignant melanoma of the female urethra is reported. Physical examination and visceral studies confirmed the primary character of the tumour and histologic examination proved it to be nodular malignant melanoma. Less than 100 cases have been previously reported. The role of immunohistochemical stains to substantiate the diagnosis is stressed. Therapy and prognosis are briefly discussed.

Primary malignant melanoma of the female urethra

BACKGROUND

Malignant melanoma is one of the rarest tumors of the female urethra. The prognosis of urethral melanoma is poor.

METHODS

A 59-year-old woman underwent total urethrectomy, bilateral inguinal lymph node dissection, and vesicostomy for Stage A primary malignant melanoma of the urethra. She received adjuvant therapy consisting of dacarbazine, vincristine, cyclophosphamide, and alpha-interferon. Two years later, repair of the parastomal hernia and interposition of an isoperistaltically ileum intussusception between the bladder and the abdominal wall were done.

RESULTS

Complete continence was achieved, and the patient catheterizes herself every 3-5 hours during the day and once at night without difficulty. She has survived 5 years without any evidence of tumor recurrence.

CONCLUSIONS

There have been only six case reports of women with primary malignant melanoma of the urethra surviving more than 5 years, including this case. Total urethrectomy with bilateral inguinal lymph node dissection should be done as the initial form of the treatment in patients with this disease who have no evidence of distant metastasis. The postoperative adjuvant therapy, consisting of alpha-interferon and chemotherapy, should be administered immediately; therefore, vesicostomy was done because it is a simple procedure. However, this type of urinary diversion requires an external appliance. Clinicians should consider the patient's quality of life, prognosis, and general condition and attempt to solve the problems of patients 2-3 years after the operation.

Primary melanoma of urinary bladder

The fourth case of primary melanoma of the bladder is presented together with a review of the previously reported cases and the relevant literature on malignant melanoma in urology. The criteria for classification of the bladder lesion as the primary site are discussed. The eighty-one-year-old female patient was felt not to be suitable for extensive surgery and was successfully treated with a combination of radiation and immunotherapy with recombinant alpha 2 interferon. After previous monthly recurrences of the tumor the patient is in complete remission fifteen months after initiation of therapy. It appears that this form of treatment might be a valuable alternative to radical surgery in elderly patients.