Melanoma of the Vagina: Case Report and Systematic Review of the Literature.

BACKGROUND: Primary melanoma of the vagina (PMV) is a rare entity. The prognosis of women with PMV is poor and there is no standardized therapy for this type of malignancy. We present the case of a 72-year-old woman with PMV (cT2, pN0, M0).

CASE REPORT: Imaging studies showed no evidence of regional or distant metastases. Molecular analysis demonstrated wild-type B-Raf proto-oncogene, serine/threonine kinase (BRAF). Staging laparoscopy with pelvic lymphadenectomy and subsequent radiotherapy with 60 Gy delivered as pelvic teletherapy and vaginal brachytherapy was applied. Systematic literature review: A total of 805 cases of PMV were identified. Most lesions were melanotic (65%) and localized (66%), whereas amelanotic (35%) and primary advanced lesions (34%) were only seen in a minority of patients. BRAF mutation was detected in none out of 33 cases, tumor protein 53 (TP53) mutations and mast/stem cell growth factor receptor CD117 (KIT) amplification were identified in one case each. The most common treatment was surgery, reported in 43% of cases. Surgery combined with adjuvant radiotherapy, adjuvant immunotherapy (mostly with interferon-alpha), or adjuvant chemotherapy were given in 35%, 8%, and 3% of cases, respectively. Radiotherapy or chemotherapy as sole treatments were used in 5% and 1% of patients, respectively. Among patients with recurrence, chemotherapy (mostly dacarbazine) alone or in combination with surgery, radiotherapy or immunotherapy was the most common treatment in 61% of cases. The mean durations of recurrence-free and overall survival were 16.4 and 22.2 months, respectively.

CONCLUSION: PMV is a rare malignancy with a poor prognosis. Surgery, radiotherapy, and immunotherapy with interferon-alpha are the mainstay of treatment for localized disease, while chemotherapy with dacarbazine is mostly used for unresectable and recurrent disease. No data on the clinical value of immune checkpoint inhibitors in PMV have been published.