[Autoradiographic study of cancer of the rectum before and after radiotherapy]

Prolifirative activity of rectum cancer cells was investigated with the help of 3H-thymidine in 13 patents before and after radiotherapy in doses 2000-4000 rad. It was established that index of the label depended upon the degree of differentiation of a tumour and was in the range of 10.3 to 21%. Preoperative irradiation in a dose of 2000 rad caused a slight decrease in the label index (8.7-19%), but affected markedly the intensity of inclusion of the preparation. Radiotherapy in a dose of 4000 rad brought about a well pronounced reduction in the label index (3.1%) and in the intensity of labelling.