Targeting chemotherapy for intrahepatic periductal lymphatic invasion by mitomycin C adsorbed to activated charcoal in hepatic hilar bile duct cancer.

A new dosage form of anticancer agent, mitomycin C adsorbed to activated charcoal (MMC-AC), was evaluated in the rabbit model of hepatic hilar bile duct cancer. The model was produced by inoculation of VX2 cells into the wall of the hepatic hilar bile duct. Histologic examination revealed that the mode of spreading of VX2 cells in the model closely resembles that of human bile duct cancer. On the other hand, selective accumulation of MMC-AC into the lymphatic vessels around the intrahepatic bile duct was observed after its injection into the hepatic hilum in rabbits. To assess the anticancer effect, 1 ml of MMC-AC was injected into the bile duct wall near the VX2 tumor. The numbers of lymphatic vessels where necrosis of VX2 cells was observed in one-third or more were 34 of 103 vessels 0.5 cm away from the tumor, 23 of 80 vessels 1.5 cm away, and 9 of 67 vessels 2.5 cm away. We believe that the injection of MMC-AC into the hepatic hilum can be effective adjuvant therapy for hepatic hilar bile duct cancer.