Immunotherapy in gastrointestinal malignancies
Recent reports of efficacy of immune therapies in solid tumors other than melanoma and renal cell carcinoma have raised enthusiasm for testing immunotherapy in gastrointestinal (GI) malignancies. Strategies under development include antibodies and related molecules that mediate cellular cytotoxicity, vaccines intended to activate tumor-specific T cell and antibody responses, adoptive transfer of natural killer (NK) cells, tumor infiltrating lymphocytes, and chimeric antigen receptor T cells, and immunomodulatory drugs such as checkpoint blocking antibodies. Thus far, benefit has been modest although insights from these studies have provided new directions for testing. We will review the current status of the various immunotherapy approaches undergoing testing in GI malignancies.