Autoradiographic studies on DNA synthesis in renal carcinoma after preoperative radiation

In order to study, autoradiographically, DNA synthesis in tumors, kidneys containing renal carcinomas were for the first time perfused with normothermic oxygenated blood with an addition of radioactively labelled thymidine. Tumor cells preserve the ability of synthesizing DNA in spite of an unavoidable postoperative ischemia. In most cases the incorporation of 3H-TdR was inhibited significantly after preoperative irradiation with a total dose of 1,600 rad applicated 48 h before operation.