Purpose: An allogeneic polyvalent melanoma cell vaccine (PMCV) has been shown to be efficacious in improving overall survival of patients with malignant melanoma in a phase II clinical setting. The PMCV consists of three allogeneic melanoma cell lines. The objectives of the study were to determine (1) whether the survival of melanoma patients who received PMCV was related to the patient's human leukocyte antigen (HLA) class I phenotype matching the HLA class I phenotype of the PMCV, and (2) whether PMCV clinical efficacy was correlated to melanoma patients with a particular HLA phenotype(s).
Materials and methods: PMCV was given to 69 melanoma patients with American Joint Committee on Cancer (AJCC) stage I to IV disease status. The PMCV and patients lymphocytes were typed for HLA-A and -B. A correlation was made between the HLA expression of PMCV lines and the HLA of patients to their survival status. A second correlation was made between the HLA of patients and survival independent of the PMCV HLA phenotype.
Results: Patients whose HLA phenotype (A3/11 and B7/44) matched the PMCV lines had a better overall survival (P < .029). Analysis of HLA expression of patients independent of PMCV HLA to survival showed that HLA-A25 phenotype patients had a significantly better overall survival (P = .006). HLA-B35 patients had a poorer survival outcome (P = .019).
Conclusion: The studies indicate that overall survival following PMCV treatment in melanoma patients significantly correlates with their HLA phenotypes. These correlations may be related to the host immune response to the PMCV or due to differences in the clinical course of melanoma in patients with different HLA types.