Destruction of VX2 tumor in rabbits by hyperthermia plus bleomycin suspended in sesame oil.

The combined antitumor effects of local hyperthermia and a simultaneous injection of bleomycin suspended in sesame oil (BLM-sesame oil) into the proper hepatic artery were studied in a model of liver cancer in rabbits. Fourteen days after inoculation of VX2 carcinoma into the left anterior lobe, 107 rabbits were used for the experiments. Local hyperthermia of 43-47 degrees C for 20 minutes was administered directly to the liver tumor via a 915 MHz microwave. In a preliminary study, administration of sesame oil alone into the proper hepatic artery led to a peripheral hepatic artery embolization, as evidenced by microangiography, and to the inhibition of tumor growth. The tumor-bearing rabbits were placed into groups of six. The first group was treated with hyperthermia, the second with a saline solution of bleomycin given intra-arterially, the third with a combination of hyperthermia and a saline solution of bleomycin given intra-arterially, the fourth with BLM-sesame oil given intra-arterially, the fifth with a combination of hyperthermia and sesame oil given intra-arterially, and the sixth with a combination of hyperthermia and BLM-sesame oil given intra-arterially. Consequently, the concomitant application of hyperthermia and intra-arterial injection of sesame oil led to a prominent inhibition of tumor growth, as compared with each modality alone (P less than 0.001). The most significant effect was obtained in the case of a combination of hyperthermia and BLM-sesame oil, as compared with a combination of hyperthermia and sesame oil (P less than 0.001). Local hyperthermia concurrent with the blockage of blood flow supplying the tumor led to a prominent inhibition of tumor growth, and addition of bleomycin to this regimen had an even greater antitumor effect. Thus, a combination of hyperthermia and chemoembolization with BLM-sesame oil is an effective treatment for liver cancer, at least in rabbits.