Cancer vaccines for hematologic malignancies.

BACKGROUND Improvements in the identification of tumor-associated antigens and in our understanding of the mechanisms regulating antitumor immune responses have revived interest in the use of therapeutic cancer vaccination. Due to their unique characteristics, hematologic malignancies represent an ideal target for vaccine-based therapeutic interventions. METHODS A review of published vaccine studies in experimental models as well as the results of clinical trials using vaccines for patients with hematologic tumors is presented. RESULTS Tumor vaccine strategies can be divided into two categories: antigen-specific strategies, in which the tumor antigens have been identified and can be isolated to develop a molecularly defined vaccine, and cellular or non-antigen-specific, in which the tumor-specific antigens are unknown but presumed to exist within the material used to generate the vaccine. Early clinical trials have shown not only the feasibility and safety of either approach but also the obstacles in therapeutic cancer vaccination as an effective treatment modality for hematologic malignancies. CONCLUSIONS Active immunization using current cancer vaccine approaches is feasible and safe. Although no major successes have been reported, the positive clinical results observed in some patients support the potential for therapeutic cancer vaccination in the management of hematologic malignancies. Results of studies that are testing vaccine formulations, targets, and settings (eg, bone marrow transplantation) may support the use of cancer vaccination as an efficient therapeutic strategy against tumors of hematologic origin.