**5. Development of dendritic cell vaccines for the treatment and prevention of cancer**

The concept of producing a vaccine aimed at specific breast cancer antigens is theoretically straightforward although the details and execution are obviously complex to carry out. There are several different vaccine approaches under investigation for the treatment of early and late stage breast cancer (dendritic cells, whole tumor cells, peptide-based and viralbased) [72, 73]. Breast cancer vaccines utilizing all of these different strategies are in various stages of development [18, 38, 72-74]. A comprehensive review of the published data on all breast cancer vaccines is beyond the scope of this chapter.

The advent of dendritic cell (DC) vaccines, propelled by the ability to culture human DC cells, has provided promise for a novel vaccine strategies [75]. Despite preclinical evidence and high expectations for the potential effectiveness of DC-based cancer vaccines, initial results of clinical trials were somewhat disappointing with discordant tumor response rates [43, 76, 77]. However, continued interest in therapeutic possibilities of DC vaccines has led to recent successes and promising data in breast and other cancers. The efficacy of DC vaccines continues to improve as efforts have been made to optimize DC vaccines and circumvent tumor escape mechanisms.
