[Histological diagnosis, DNA-content and chromatin pattern of breast cancer cases with positive and negative 17-beta-oestradiol receptor binding (author's transl)].

The DNA-concent of cell nuclei of 45 breast cancer cases of various histological structure has been determined cytophotometrically. With the exception of two gallert carcinomas no DNA-histogram of peridiploid range was found. The average DNA-content was 2--3 times higher as in the control tissue. The standard deviation of undifferentiated solid mammary tumors was the highest measured in this series. 24 of 45 cases had a negative oestrogen receptor binding. This was true in 60% of the undiffierentiated solid breast cancer cases, in 69% of the adenomatous and in 89 respectively 67% of the ones of special histological structure. The heterochromatin content of nuclei was lowest in the group of differentiated mammary cancer (50--60%). In the group of undifferentiated tumors it was 60--70%. So much for now is known about the mechanism of cellular action of 17-beta-oestradiol and the function of eu- and heterochromatin of cell nuclei it is discussed that positive or negative oestrogen hormone receptor binding in mammary tumor cells is probably a biochemical parameter of cytological desintegration. From this point of view these hormon receptors could be of the same value as the index of Barr bodies in breast cancer cells with respect of selection of cases for hormonal therapy. But this has to be analyzed in further studies extensively.