Liquid 2-P-HEMA for endovascular tumor therapy: in vivo feasibility study

To evaluate a new liquid polymer developed for selective arterial tumor embolization.

In six rabbits we embolized the renal artery with pure 2-P-HEMA. Three rabbits were killed immediately after embolization, one after 12 h, and two animals underwent follow-up angiography after two weeks. In a second part of the study we embolized the left renal artery in three mini-swine with pure 2-P-HEMA. The kidneys were examined post mortem by soft-tissue radiography and kidney-tissue section microscopy.

Complete occlusion of small distal arteries, most of the arterioles together with the precapillary vascular bed, was achieved in all animals. The speed of injection influenced the grade of distal occlusion; repeated injections through the same microcatheter were possible. The relatively fast injection speed of 0.3 ml/min led to an optimal distribution of the liquid embolic. There was no reperfusion in the two follow-up angiographies two weeks after embolization. Histopathologically, there was no angionecrosis and subintimal bleeding. No marked inflammatory reaction in the vessel wall or perivascular tissue was observed in the embolized arteries.

This study suggests that liquid 2-P-HEMA may be feasible for the treatment of tumors.