[Development of a slow release system of anti-cancer drugs retained in calcium-hydroxyapatite ceramic].

A new type of anticancer material with sustained release by enclosure of cisplatin (CDDP) into porous calcium hydroxyapatite ceramic (CDDP-CHA) was developed. A slow release of anticancer drug from CDDP-CHA was confirmed in in vitro experiments. When this material was implanted into normal thigh muscle of mouse, a sustained release of CDDP was observed during over 8 weeks after implantation. The diffusion of drug into blood and other organs from the implanted site was very small. CDDP-CHA placed into the implanted tumor of mouse allowed a slow release and high drug level from the material in the tumor. The concentration of the drug in other organs such as liver and kidney was very low compared with that of the tumor. These results suggest that this material has an important role for cancer chemotherapy, particularly in bone tumors for the reasons of calcium hydroxyapatite ceramic carrier having a mechanical strength.