[Character of a human cholangiocarcinoma CHGS, serially transplanted to nude mice]

With the progress in surgical technique, remarkable improvement has been noted in the treatment of bile duct carcinoma. However, in the cholangiocarcinoma at porta hepatis or in the progressive carcinoma, many cases have been reported, for which radical surgery is not achievable. In recent years, discussion has been concentrated on the necessity of multidisciplinary treatment for the bile duct carcinoma, but fundamental research has not been done enough. In the present paper, the process for obtaining CHGS strain implantable to the nude mouse derived from a human cholangiocarcinoma as achieved in our department was discussed, and its biological characteristics-above all, the sensitivity to carcinostatic agents and to radiation-were evaluated. The doubling time of CHGS strain is 6.2 days, and nude mice showed stable proliferation with 100% viability. Histologically, it was tubular adenocarcinoma similar to the primary tumor. It has high mucin producing ability, and necrosis hardly occurs. The search for DNA ploidy by flow cytometry revealed the presence of two types of cells: The cells of diploid pattern and aneuploid pattern. In the tests to determine the sensitivity of CHGS strains to carcinostatic in MMC, ADR, 5-FU and CDDP groups, and to radiation according to the Battele Columbus Laboratories Protocol, the regression of tumor was observed in MMC, ADR, CDDP groups. Particularly, in MMC group, some of the tumors had disappeared. Recurrence was also noted in this case, but the survival, was still recognized nearly four years after the operation through the postoperative auxiliary therapy. This was regarded as the case, where the sensitivity test using the nude mouse implantable tumor strain was reflected well in clinical application.