[In-vitro-technique for autoradiographic investigations of cell proliferation in benign and malignant alterations of the human urinary bladder mucosa from biopsy specimens (author' transl)].

An in-vitro double labelling technique with 3H- AND 14C-Thymidine was applied to biopsy specimens of the human urinary bladder mucosa in order to determine proliferation kinetics of normal bladder epithelium as well as its benign and malignant alterations. Application of above mentioned technique led to evaluable autoradiographs. The mean 3H-Thymidine labelling-index in bladder cancer was remarkably higher than in normal bladder epithelium and in benign papillomas. There was a good correlation between histologic grading of malignancy and increase of the mean 3H-Thymidine labelling index. Addition of 5-Fluorodesoxyuridine to the incubation medium had no influence on the labelling of the incubated tissue.