Intraperitoneal immunotherapy of peritoneal carcinomatosis

Carcinomas that originate in the ovary or from different sites in the gastrointestinal tract frequently develop metastases that involve the peritoneal and serosal surfaces. Carcinomatous involvement of the peritoneum is a significant cause of morbidity and mortality. Advances in our understanding of the immunobiology of the peritoneal cavity and the availability of technically advanced immunotherapeutic agents are providing an important opportunity for the intraperitoneal delivery of these agents. This review describes newer concepts in tumor immunology that have a bearing on the further development of intraperitoneal immunotherapy; delivery systems for and issues to be resolved in intraperitoneal immunotherapy, and results of studies with recombinant interferons alpha and gamma and interleukin (IL)-2, cellular therapies including lymphokine-activated killer cells, tumor-infiltrating lymphocytes, monoclonal antibodies, and intraperitoneal radioimmunotherapy. New trials of intraperitoneal immunotherapy employing novel agents, including IL-12 and genetically modified tumor vaccines, are discussed, as are issues related to the integration of immunotherapy with standard chemotherapy agents. A number of immunotherapy agents have been tested intraperitoneally and have shown promising clinical activity with acceptable toxicity. Complete responses have been documented at surgical restaging, and intraperitoneal treatments with these agents may soon be included in the therapeutic armamentarium for patients with peritoneal carcinomatosis.