Summary: Interleukin-2 (IL-2), a natural expander of lymphocytes, exerts its physiological effect mainly on local and regional levels. Its anticancer activity has to be interpreted as contributing to the concerning action of cytokines and activated cellular effectors in the tumor site and in context with tissue or organ microenvironment. Therapeutically, however, IL-2 has become popular in systemic treatment which combines IL-2, interferon-alpha, and cytostatic drugs in renal carcinoma and malignant melanoma. Systemic application requires relatively high doses of IL-2 and is associated with remarkable toxicity arising from widespread non-specific activation of the immune system and release of cytokines. In contrast, local or regional admi-nistration of IL-2 are rarely accompanied with adverse effects and the dosage can be substantially reduced. Current experience with intratumoral, peritumoral, intrarterial, intraportal, intrasplenic, intraperitoneal, intrapleural and intrapericardial deliery of IL-2 is reviewed with special emphasis given to regional intrahepatic chemomunotherapy of liver tumors.
Locoregional Application of Interleukin-2 in Solid Tumors
