15 Radiation with targeted agents

Abstract

At present, the systemic treatment of unresectable colorectal cancer liver metastases involves oxaliplatin and irinotecan–based chemotherapy regimens combined with targeted therapies such as bevacizumab (Avastin) and cetuximab (Erbitux). Radiation therapy, traditionally, is not considered a viable treatment modality owing to its unacceptably high hepatic toxicity, and still steering traditional wisdom or dogma that chemoradiation cannot be an oncological strategy for a stage IV disease. Selective internal radiation treatment with yttrium-90 (Y-90) radiomicrospheres has emerged as an effective liver-directed therapy with a favorable therapeutic ratio. Since its early clinical trials, it has demonstrated improved response rates when used in conjunction with systemic or regional chemotherapy. This article reviews the clinical role for Y-90 radiomicrosphere therapy in the contemporary management of colorectal cancer liver metastases. All the structured clinical trials, to date, are summarized, including those that studied the value of combined Y-90 radiomicrosphere therapy and current chemotherapy protocols.