Primary malignant melanotic melanoma and hypomelanotic melanoma of the female urethra: case series and a review of the literature in China

Primary malignant melanoma of the urethra: Report of 9 cases in China

BACKGROUND

Primary urethral melanoma is extremely rare and malignant, and accounts for <1% of all melanoma cases. Here, we aimed to gain more insight into the pathological and follow-up outcomes of patients with this tumor type.

METHODS

We conducted a retrospective analysis of nine patients who had undergone comprehensive treatment at West China Hospital since 2009. Furthermore, we also performed a questionnaire-based survey to determine the quality of life and health statuses of surviving patients.

RESULTS

Most participants were women, and their ages ranged between 57 and 78 years (mean age: 64.9 years). Common clinical presentations included pigmentation, moles, and irregular neoplasms in the urethral meatus with or without bleeding. The final diagnosis was based on pathological and immunohistochemical examination results. All patients underwent regular follow-ups after receiving surgical or non-surgical therapy, such as chemotherapy or radiotherapy.

DISCUSSION/CONCLUSION

Our study revealed that pathological and immunohistochemical tests are crucial for precise diagnosis, especially in asymptomatic patients. Primary malignant urethral melanoma generally has a poor prognosis; therefore, early and accurate diagnosis is imperative. Timely surgical intervention and immunotherapy can help improve patient prognosis. Moreover, an optimistic outlook and family support may augment the clinical management of this disease.

[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.

Progress in the treatment of urethral adenocarcinoma

BACKGROUND

Urothelial adenocarcinoma (UA) is a rare subtype of primary urothelial carcinoma, which is more common in women and has a poor prognosis. Because of their low incidence, most of the existing literature is based on case reports and there is a lack of comprehensive literature on this type of tumor.

PURPOSE

This article provides a comprehensive and systematic review of the epidemiology, pathological types, treatment, and prognosis of UA. Especially in the treatment section, we reviewed the various treatment methods including surgery, radiotherapy, chemotherapy, immunotherapy and molecular targeted therapy. This review aims to provide a theoretical basis for the clinical diagnosis and management of UA.

METHODS

We reviewed the relevant literature of UA from Pubmed.

CONCLUSION

There is no standard treatment for UA. Multidisciplinary therapy, including surgery, radiotherapy and chemotherapy, is the current trend. Immunotherapy and molecular targeted therapy will also become viable options for the treatment of UA in future.

Intra-Abdominal Malignant Melanoma: Challenging Aspects of Epidemiology, Clinical and Paraclinical Diagnosis and Optimal Treatment—A Literature Review

According to European consensus-based interdisciplinary guidelines for melanoma, cutaneous melanoma (CM) is the most deadly form of dermatological malignancy, accounting for 90% of the deaths of skin cancer patients. In addition to cutaneous melanoma, mucosal melanoma occurs in four major anatomical sites, including the upper respiratory tract, the conjunctiva, the anorectal region, and the urogenital area. As this cancer type metastasizes, a classification used in the current medical literature is the distinction between secondary lesions and primary malignant melanoma of the abdominal cavity. Given that malignant melanoma is the most common cancer that spreads to the gastrointestinal tract, different imaging modalities compete to diagnose the phenomenon correctly and to measure its extension. Treatment is primarily surgery-based, supported by immunotherapy, and prolongs survival, even when performed at stage IV illness. In the end, special forms of malignant melanoma are discussed, such as melanoma of the genito-urinary tract and amelanotic/achromic melanoma. The importance of this present literature review relies on yielding and grouping consistent and relevant, updated information on the many aspects and challenges that a clinician might encounter during the diagnosis and treatment of a patient with intra-abdominal melanoma.

Immune checkpoint inhibitor in a case with primary urethral adenocarcinoma with lung metastasis

Primary urethral adenocarcinoma is extremely rare, and the clinical experience in optimizing the management is limited. The efficacy of immune checkpoint inhibitors for these patients is not clear. Here, we describe a 52-year-old patient with primary urethral adenocarcinoma accompanied by inguinal lymph nodes and lung metastasis with progressive disease after radiotherapy and multiline chemotherapy. The expression of programmed cell death ligand-1 (PD-L1) was positive. Hence, this patient was treated with tislelizumab, an immune checkpoint inhibitor. The disease is well controlled and the overall survival time is 5 years. Moreover, the patient tolerated the treatment well. To our knowledge, this is the first reported case in which immunotherapy was used for primary urethral adenocarcinoma. The immune checkpoint inhibitors may be a novel option for the treatment of these patients.

Diffusion-Weighted Imaging Combined with Perfusion-Weighted Imaging under Segmentation Algorithm in the Diagnosis of Melanoma

This study is aimed at exploring the value of magnetic resonance diffusion-weighted imaging (DWI) combined with perfusion-weighted imaging (PWI) for diagnosing melanoma under a three-dimensional (3D) hybrid segmentation algorithm. 40 patients with melanoma were collected as research objects and subjected to magnetic resonance imaging (MRI) examination. A segmentation model was constructed and the original images were input. The noise contained in the images was preprocessed and normalized, and the mixed level set segmentation was performed after linear fusion of the images. Imaging findings were analyzed to find that the combined diagnosis of DWI and PWI with a 3D hybrid segmentation algorithm had the advantage of being clear and accurate. 10 primary cases were detected, which occurred in the cerebral meninges; 30 cases of metastases occurred inside the skull, mostly adjacent to the surface of the brain. The typical T1-weighted imaging (T1WI) and T2-weighted imaging (T2WI) of melanoma showed high signal and low signal, respectively, and the enhanced scan showed obvious enhancement. Atypical melanoma was manifested variously in MRI; a few had cystic necrosis, and an enhanced scan of the solid area revealed significant enhancement. Patients with multiple metastatic melanomas mainly showed low signal on DWI, and patients with primary or single metastatic melanoma mainly showed high signal or mixed high signal. Patients with perfusion imaging showed high perfusion on PWI. The 3D hybrid segmentation algorithm helped to improve the accuracy of DWI combined with PWI in the diagnosis of melanoma. This work provided a certain reference for the clinical diagnosis of melanoma.

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.

STAT3 activates the transcription of lncRNA NR2F1-AS1 to promote the progression of melanoma via regulating the miR-493-5p/GOLM1 axis

BACKGROUND

Long non-coding RNAs (lncRNAs) are vital regulators during the biological processes of melanoma. The present study aimed to uncover biological functions of lncRNA termed NR2F1 antisense RNA 1 (NR2F1-AS1) in melanoma and the potential mechanisms.

METHODS

Relative levels of NR2F1-AS1 and miR-493-5p in a total of 137 paired primary melanoma tissues and corresponding non-tumor tissues, as well as three melanoma cell lines, were examined by a real-time polymerase chain reaction. The clinical significance of NR2F1-AS1 expression was analyzed statistically. The STAT3 binding motif in the promoter region of NR2F1-AS1 was identified by JASPAR (http://jaspar.genereg.net). The association between STAT3 and NR2F1-AS1 was determined by dual-luciferase reporter and chromatin immunoprecipitation assays. The effects of NR2F1-AS1 on cell proliferation, migration and were measured by cell counting kit-8 (CCK-8), Edu, transwell and wound healing assays. Dual-luciferase reporter and RNA pull-down assays were applied to validate the interaction among NR2F1-AS1, miR-493-5p and GOLM1. Furthermore, in vivo experiments were conducted to demonstrate the oncogenic role of NR2F1-AS1 in melanoma.

RESULTS

Up-regulated NR2F1-AS1 and down-regulated miR-493-5p were detected in melanoma tumors and cells. The overexpression of NR2F1-AS1 was induced by STAT3. High NR2F1-AS1 expression was correlated to advanced tumor stage and poor prognosis of melanoma. Functional studies using CCK-8, Edu, transwell and wound healing assays revealed that the proliferative, migratory and invasive capacities of melanoma cells were attenuated by the by inhibition of NR2F1-AS1. Moreover, NR2F1-AS1 was able to up-regulate GOLM1 through recognizing and binding miR-493-5p. Furthermore, knockdown of miR-493-5p distinctly reversed these inhibitory effects of NR2F1-AS1 down-regulation on the tumorigenesis and progression of melanoma.

CONCLUSIONS

Our findings demonstrate a key role for NR2F1-AS1 in melanoma progression via targeting miR-493-5p/GOLM1 axis.

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.

Amelanotic Malignant Melanoma of the Male Urethra: A Potential Diagnostic Pitfall

A rare disease in an unusual site can closely mimic a typical presentation of a common disease, sometimes with devastating consequences. We present a case of primary amelanotic malignant melanoma of the urethra in a male, with clinical and histological characteristics that could have led to a mistaken diagnosis of high-grade urothelial carcinoma. Amelanotic mucosal melanoma should be suspected in all cases of high-grade mucosal tumors with practically any appearance (epithelioid, sarcomatoid, anaplastic, mixed). Morphological hints pointing toward melanoma-such as the presence of sparse melanin pigment or melanoma in situ-should be sought, and if absent, an immunohistochemical panel comprising S100 and HMB45 should be performed.