Primary melanoma of the prostate: case report and review of the literature

Melanoma of glans penis and urethra: A case report and systematic review of the literature of a rare and complex neoplasm

OBJECTIVE

To evaluate the features and prognosis of melanoma of glans penis and urethra, with the presentation of a significant case report.

MATERIALS AND METHODS

A systematic literature review was performed using the MEDLINE (PubMed) and Cochrane Libraries databases to identify all cases of male mucosal melanoma reported.

RESULTS

Two hundred fifty-two patients with male mucosal primary melanoma were found. Glans penis and fossa navicularis as primary site includes the 81.6% of all lesions considered. Median Breslow's depth is 2.1 mm, whereas nine in situ melanomas have been reported. At the diagnosis, the disease was at a non-localized stage in 21.4% for glans penis melanomas and 11.7% urethral lesions, respectively. The 2 and 5-year survival for glans melanoma is 62.5% and 38.4%; higher rates were observed in the 2012-2020 period (76% and 58.8%, respectively). Two-year survival for urethral melanomas is 66.7%, while 5-year survival is 12.5%. 22 patients survived over 5 years with a Breslow's depth reported always < 3.3 mm.

CONCLUSION

Melanoma of the glans penis and urethra is a rare neoplasm associated with a poor prognosis, however recent reports show higher survival rates. Surgery remains the mainstay for a localized disease. Taking into account the small number of cases reported, topical imiquimod seems to be a valid non-surgical alterative for melanoma in situ. The use of immunotherapy and targeted therapy should be considered only in an adjuvant setting according to the recommendations of cutaneous melanoma; however, additional clinical data on male mucosal melanoma are needed to draw definitive conclusions.

Malignant melanoma of the prostate: Primary or metastasis? A case report

BACKGROUND

Malignant melanoma of the prostate is rare. Twenty-five studies describing 45 cases have been reported. Prostate melanoma is characterized by an insidious onset and poor prognosis. The prognosis and treatment vary according to primary or secondary melanoma.

CASE SUMMARY

A 75-year-old man attended the hospital due to low back pain of 2 mo duration. He denied a history of trauma or abnormal urinary symptoms. Digital rectal examination showed indentation in the left lobe of the prostate, 1 cm in diameter. His prostate-specific antigen was 5.6 ng/mL and 18F-fluorodeoxyglucose positron emission tomography computed tomography (18F-FDG-PET/CT) showed focal glucose metabolism in the left lobe. Imaging showed bone metastases to T12 and bilateral ribs. Transperineal prostate biopsy was done and three tissue specimens on the left side showed prostate adenocarcinoma (Gleason score 3 + 3 = 6), but the specimen on the right side showed malignant melanoma. The patient underwent T12 tumor resection and pathology findings indicated metastatic malignant melanoma. The patient underwent gastroscopy and colonoscopy, and gastroscopy revealed multiple mucosal black spots in the gastric body and fundus. The patient was diagnosed with secondary malignant prostate melanoma and primary gastric disease.

CONCLUSION

Diagnosis of primary prostate melanoma requires caution and 18F-FDG-PET/CT may result in false-negative detection of melanoma.

Anorectal and Genital Mucosal Melanoma: Diagnostic Challenges, Current Knowledge and Therapeutic Opportunities of Rare Melanomas

Mucosal melanomas (MM) are rare tumors, being less than 2% of all diagnosed melanomas, comprising a variegated group of malignancies arising from melanocytes in virtually all mucosal epithelia, even if more frequently found in oral and sino-nasal cavities, ano-rectum and female genitalia (vulva and vagina). To date, there is no consensus about the optimal management strategy of MM. Furthermore, the clinical rationale of molecular tumor characterization regarding BRAF, KIT or NRAS, as well as the therapeutic value of immunotherapy, chemotherapy and targeted therapy, has not yet been deeply explored and clearly established in MM. In this overview, focused on anorectal and genital MM as models of rare melanomas deserving of a multidisciplinary approach, we highlight the need of referring these patients to centers with experts in melanoma, anorectal and uro-genital cancers treatments. Taking into account the rarity, the poor outcomes and the lack of effective treatment options for MM, tailored research needs to be promptly promoted.

Imaging of non-epithelial neoplasms of the prostate

The purpose of this article is to review the spectrum of rare non-epithelial tumors of the prostate. This focused article will help the readers to understand the imaging findings of such rare entities attributed to their clinicopathological features. Radiologists must be familiar with the spectrum of non-epithelial tumors of the prostate, which helps to suggest alternate diagnosis other than adenocarcinoma, when imaging features are atypical. This is important because these tumors have different management approaches and prognoses when compared to adenocarcinoma of the prostate.

Cutaneous malignant melanoma with rarest combination of prostatic and splenic metastases on fluorodeoxyglucose (FDG) positron emission tomography-computed tomography scan

Cutaneous malignant melanoma (MM) metastases to prostate and spleen are very rarely experienced in clinical setting. As per our knowledge, coexistence of prostate and splenic metastatic MM is not reported worldwide. We are presenting a case of 70-year-old male patients with biopsy and clinically proven case of multifocal cutaneous malignant melanomatous lesions having multiple metastatic lymph nodes and systemic metastases, including prostate and spleen. This is the first case reported worldwide having a combination of prostate and splenic metastases.

Detection and Treatment of Primary Prostatic Melanoma

OBJECTIVE

To describe a case of primary melanoma of the prostate gland, then review the published literature of similar cases.

METHODS

Presentation of the clinical course of a 42-year-old man diagnosed with primary melanoma of the prostate after presenting with gross hematuria. Review of published literature.

RESULTS

Primary melanoma of the genitourinary tract is a very rare disease, representing less than 1% of all melanomas in men. Only 6 cases of primary melanomas have been previously reported in the English literature.

CONCLUSION

The current report emphasizes the importance of a multidisciplinary approach and adherence to treatment principles in cutaneous melanoma. With complete surgical extirpation (including extended pelvic lymphadenectomy as needed), close surveillance using 18F-FDG PET/CT, and aggressive systemic treatment in patients with good performance status, cure can be achieved.