 Studies of low-dose, protracted administration of Irinotecan and other camptothecin analogues in mice bearing xenografts of human tumors have shown less toxicity and equal to or better antitumor activity than shorter, more intense dosing schedules. With the proposed device, the in-vivo and pre-clinical data shows that there is reduced systemic levels of Irinotecan, when delivered to tumorous tissue following embolization, and a longer, sustained concentration of the active metabolite, SN-38. 