Primary amelanotic melanoma of the vagina.

BACKGROUND: Primary malignant melanoma of the vagina is extremely rare, accounting for 0.3-0.8% of all malignant melanomas. True amelanotic vaginal melanoma showing no melanin on histological examination is exceedingly rare, accounting for only 2% of all vaginal melanomas. CASE REPORT: We describe a 31-year-old female patient who presented with locally advanced amelanotic melanoma of the vagina, with no evidence of metastatic spread on the computerized tomography (CT) scan, but who was subsequently diagnosed as suffering from metastatic disease by positron emission tomography (PET)-CT performed a few weeks following posterior pelvic exenteration. CONCLUSION: Specific immunohistochemical staining with melanoma markers should be performed to confirm or exclude a diagnosis of amelanotic melanoma in all patients presenting with a vaginal mass composed of undifferentiated epithelioid malignant cells. Fluorodeoxyglucose (FDG)-PET-CT should be performed as part of the preoperative evaluation, to identify the presence or absence of metastatic disease in all patients with vaginal melanoma.

Immune Monitoring of Patients Treated With a Whole-Cell Melanoma Vaccine Engineered to Express 4-1BBL.

CD8 lymphocytes are mandatory mediators of tumor regression. To enhance their specific antitumor activity, we aimed to improve a melanoma cell-based vaccine by transfecting it with 4-1BB ligand, a costimulatory and immune modulatory molecule. Thirty-four American Joint Committee on Cancer (AJCC) stage IIB-IV patients were vaccinated with a melanoma antigen-rich cell line engineered to express HLA-A2 and 4-1BBL (M20/A2/BBL). Twelve serially recruited patients were monitored for interferon γ expression and CD107a mobilization before and after vaccination. Thirty-three patients remained alive, with an estimated mean overall survival of 26.2 months. No grade 3-4 adverse events were encountered. Immune monitoring detected an increase in circulating antimelanoma CD8 T cells in 9 of 12 patients, which were significantly stimulated by the parental melanoma, reflecting a relevant antitumor response. The results from this study show that the costimulatory 4-1BB ligand fortifies an antigen-rich melanoma cell line with enhanced antigen-specific stimulation of CD8 T cells. The use of a costimulatory molecule as part of a vaccine confers a selective increase of T-cell subsets with antimelanoma reactivity, which in some cases were characterized for their epitope specificity.

A single Mediterranean, possibly Jewish, origin for the Val59Gly CDKN2A mutation in four melanoma-prone families.

We have screened for CDKN2A germline mutations in 49 Jewish families with two or more cases of melanoma. The Val59Gly mutation, one of the three different alterations identified among these families, was also detected independently in two kindreds from France and one from Spain. The impact of the Val59Gly substitution on the function of the cyclin-dependent kinase inhibitor p16(INK4a), a product of the CDKN2A gene, was assessed by protein-protein interaction and cell proliferation assays and related to potential structural alterations predicted by molecular modeling. Seven microsatellite markers in the vicinity of the CDKN2A gene were used to determine whether the mutation in these families is identical by descent, or represents a mutational hotspot in the CDKN2A gene. Our results show that the Val59Gly substitution impairs p16(INK4a) function, and this dysfunction is consistent with structural predictions. All melanoma-affected individuals tested in the families under study harbor this mutation. Interestingly, the Israeli pedigree includes an affected individual who is homozygous for the Val59Gly mutation. A common haplotype of microsatellite markers has been demonstrated for mutation carriers in all four pedigrees. The Israeli pedigree and one of the French melanoma families are of Moroccan and Tunisian Jewish descent, respectively, and the other families originate from regions of France and Spain close to the Pyrenees. We conclude that the Val59Gly mutation is a major contributor to melanoma risk in the families under study and that it may derive from a single ancestral founder of Mediterranean (possibly Jewish) origin.