Interstitial Chemotherapy and Polymer-Drug Delivery

The efficacy of systemic chemotherapy for brain tumors is limited by physiologic and pathological barriers within the central nervous system. Thus, systemically intolerable doses are required to deliver and maintain tumoricidal concentrations in the brain. Local delivery of chemotherapeutic agents directly to the tumor could potentially circumvent systemic side effects. This chapter focuses on the development of interstitial chemotherapy and polymer-drug delivery. It describes the technologies being developed to circumvent the barriers encountered in delivering chemotherapeutics to the central nervous system. Special emphasis is placed on the development of the FDA-approved Carmustine (BCNU)-loaded polymer (Gliadel®) for the treatment of malignant tumors. This chapter reviews the results and implications of pre-clinical and clinical studies of Gliadel® and other polymerchemotherapeutic agent systems and describes the surgical technique used to implant Gliadel® wafers at the tumor site. Furthermore, it briefly describes new local drug delivery systems including microchip drug delivery and nanocarriers.