Yttrium-90 radioembolization for unresectable/recurrent intrahepatic c

This study’s discussion of “naive” Y90 versus Y90 after other treatments makes me wonder about the decision by Bill’s team to do three cycles of chemo before doing the Y90, which I’ve also seen described by other patients. Would that still in essence be considered “concurrent”? Or does maybe it have more to do with the amount of tumors in the liver, that the Y90 would be more effective if that load could be lessened some first?