The present disclosure relates to oncolytic viruses for use transcatheter arterial viroembolization methods. The present disclosure also provides composition with such oncolytic viruses in combination with a biocompatible microparticle or hydrophilic polymer gel agent suitable for active embolization. The present disclosure further provides methods of transcatheter arterial viroembolization using such oncolytic viruses and compositions preferably in a manner that debulks tumor.