Minimally invasive therapeutic strategies provide interesting options for the treatment of solid tumors,such as hepatocellular carcinomas (HCCs).It has become obvious,however,that straightforward embolization is generally not sufficient in oncology.Embolic occlusions can trigger local neovascularization,and the ultimate result can be that the tumor grows faster and further than would have been the case without any intervention.This insight has triggered the development of drug-eluting embolic beads.These perform two functions:embolization,and controlled slow release of a drug (e.g.,doxorubicin) in the vicinity of each embolic particle inside the tumor.