Study on the Histopathological Changes of the Subrenal Capsular Implantation of the Human Urologic Cancers

Bahk, Jong Yoon; Jeong, Seung Wha; Kim, Suk Hee

Abstract

The selection of the chemotherapeutic agents for the treatment of the urologic malignancy was one of the difficult problem in urologic practice. After the development of the in vivo sensitivity test using subrenal capsular implantation of the cancer tissue, a lot of the application of this assay were performed in various field of the advanced malignancies. We examined the histopathological changes of the implanted urologic cancer tissues under the renal capsule of the mice. The specimens, implanted under the renal capsule, were 14 cases of the bladder cancer, 2 cases of the renal cell carcinoma and one case of the prostatic carcinoma. In experiment, we used 472 immunocompetent normal mice and divide them into two groups, non-immunosuppressed normal mice and immunosuppressed group with intravenous infusion of the cyclophosphamide 200mg/kg 24 hours prior to assay. As the control group, we used athymic nude mice for human urologic cancer and C3H/He strain for MBT-2 bladder cancer. The results we found were as follow ; 1. The growth of the implanted cancer tissues was noticed in 270 mice among 291 which were sacrificed until the 6th postoperative day and the take rate was 92.8%. 2. The growth of the implanted cancer tissues was continuous until the 6th postoperative day progressively but reduced thereafter in immunocompetent group. But in immunosuppressed group, it showed progressive growth of the implanted tissue until the 8th postoperative day. The growth of the control group was similar to the immunosuppressed group, until the 6th postoperative day. 3. Calculation of the proportion of the host cellular infiltration in total dimension of the grafted tissue was done and in immunocompetent group, the 4th postoperative day group was 27.3%, the 6th postoperative group was 89.4% and the 8th postoperative group was 100%. But in contrast in immunosuppressed group, at the 4th postoperative day group was less than 10%, the 6th postoperative day was 29.4% and at the 8th postoperative day group was 91.7%. With above histopathological study, we conclude that the most easy and reasonable subrenal capsular assay(SRCA) in the in vivo chemosensitivity test for the selection of the anticancer chemotherapeutic agent for the treatment of the malignancy is the test performed under the immunosuppressed state with cyclophosphamide, 24 hours prior to SRCA, and the results is the most proper at the examination at postoperative 6th day after implantation.