The article by Laheru and Jaffee offers an excellent summary of immunotherapies for gastrointestinal malignancies. Thoughtful descriptions of the antibody, cytokine, and cel- lular components of the immune system provide useful background information that facilitates an understanding of specific passive and active cancer immunotherapies. Immunotherapies that have demonstrated efficacy in colon cancer clinical trials, including levamisole (Ergamisol), passive monoclonal antibody vaccines, and bacillus Calmette- Guérin (BCG)–autologous tumor vaccines, are appropriately reviewed. In addition, novel approaches at varying stages of clinical testing are clearly summarized; these include the use of an anti-idiotypic antibody, genetically modified tumor and dendritic cells, recombinant protein, and viral and DNA vaccines. Some additional approaches, studies, and perspectives are also worthy of mention as a supplement to this review.