Therapeutic vaccination for the treatment of malignant melanoma

With increasing knowledge of tumor-associated antigens and T cell epitopes, and the mechanisms of induction and regulation of T-cellular immune responses, therapeutic vaccination is increasingly being explored as a treatment option for cancer. Several clinical cancer vaccination trials, the majority of them with melanoma patients, have demonstrated efficient induction of tumor-specific cellular immune responses in patients. However, these immune responses, in most cases, do not translate into clinical responses. The clinical response rates in these trials are relatively low. The most likely causes for the lack of correlation of immunological and clinical responsiveness are loss of antigenicity and immune suppression. Nonetheless, many patients in the vaccination trials have experienced extended survival compared to clinical experience. Therapeutic vaccination thus appears suited for maintenance therapy where cure is not possible and is an interesting option for adjuvant therapy after surgical tumor resection. While the clinical efficacy of vaccination is expected to be better for early-stage cancer, advancement of the treatment of advanced-stage disease will require combination with other therapeutic principles.