Transarterial Chemoembolization by Hepasphere Microspheres for the Treatment of Unresectable Colorectal Liver Metastasis

Colorectal cancer is the third most frequently diagnosed cancer and the third leading cause of cancer related deaths in Taiwan. Of the 10,248 new colorectal patients diagnosed each year approximately 60% will develop liver metastasis during the course of their disease. In approximately 30% of these patients who develop liver metastasis the metastatic disease will remain confined to the liver.
For the 70-75% of colorectal patients with colorectal liver metastasis not suitable for hepatic resection or similarly ablative therapy with curative intent, systemic chemotherapy is the standard initial management. However, after a patient has failed first- line and in some cases second-line chemotherapy, response rates fall to as low as 12% (Chen HX 2006). Transarterial chemoembolization (TACE) with microsphere is an alternative treatment because normal liver tissue receives most of its blood supply from the portal vein, while colorectal liver metastases derive most of their flow from the hepatic artery. Several clinical trials have explored the feasibility and the efficacy of TACE with microsphere as a treatment for patients with colorectal liver metastasis. HepaSphere represents a novel drug delivery system for chemoembolization, which can add two benefits to embolization therapy. First, by ionically binding the doxorubicin throughout the microspheres, more drug can be delivered into the tumor, with less escape into peripheral circulation. Second, conformability to the architecture of the vessel lumen, providing more contact surface area with the embolic material and the vessel intima, leading to a more complete occlusion. However, there are limited experiences in using HepaSphere TACE for colorectal liver metastasis in Taiwan. In this pilot study, we will evaluate the initiate safety and efficacy of Hepasphere microspheres loaded with a chemotherapeutic agent doxorubicin for the treatment of patients who have failed first-line and second-line systemic chemotherapy.