Primary malignant melanoma at unusual sites: an institutional experience with review of literature

Abstract

Apart from the skin and choroid plexus, primary malignant melanoma is rare at the other sites and lacks organized documentation. Here, we have tried to enumerate the primary malignant melanomas at various atypical sites, supported by literature review. Seventeen cases were identified from our records of the past 5 years, which had detailed clinical work-up to exclude a possibility of a metastasis. A clear female predominance with involvement of the lower genitourinary tract was identified. In addition to three cases from the vagina, two cases each from the cervix, ovary and urethra, respectively, such cases were also identified in cerebral cortex (frontal and fronto-parietal area), rectum, nasal cavity, tongue, breast and tonsillar fossa. Although many were amelanotic, no specific histology was noted. In conclusion, malignant melanomas can arise in unconventional areas. Gross tumor appearance and the unavailability of an immunohistochemical panel, may result in their misdiagnosis as primary epithelial malignancies. A possible metastasis should always be ruled out.

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

“…Specifically, it is unclear if treatment strategies should follow current practice regarding female genital tract cancer or should be extrapolated from established strategies used for cutaneous melanomas (11,12). In addition, the clinical rationale of molecular tumor characterization of PMV regarding BRAF, KIT, or NRAS as well as the therapeutic value of immunotherapies and targeted therapies such as the monoclonal antibodies to the programmed cell death protein-1 (PD-1) nivolumab and pembrolizumab and the antibody to the cytotoxic Tlymphocyte-associated protein 4 (CTLA-4) ipilimumab has not been established for patients with PMV (13).…”

Malignant Vaginal Melanoma with Metastases to the Papilla of Vater in a Dialysis Patient: A Case Report

“…Less than 150 cases of primary vaginal melanoma have been reported in the literature to date. In the recent 5 years, only 3 cases have been reported (2).…”

“…This melanoma is a highly aggressive tumor with an overall 5-year survival rate of 0-20% (1). Less than 150 cases of primary vaginal melanoma have been identified in a review of literature (2). Furthermore, metastasis of a malignant tumor to the gastrointestinal (GI) tract (especially to the papilla of Vater) is uncommon.…”

Primary malignant melanoma of the female urethra: a rare case of cytological observation

“…Primary melanoma of the genitourinary tract is rare, accounting for less than 1% of all cases of melanoma [1,2], while primary malignant melanoma of the urethra in females represents only 0.2% of all malignant melanomas [3]. Since the clinical presentation of urethral melanoma is similar to that of urothelial carcinoma, there is frequently a delay in diagnosis [4].…”