RESUMO
The state of the viscosity of erythrocyte membranes in breast cancer patients (68--in menopause and 32--with menstrual cycle) was studied in comparison with the content of steroid hormone receptors in the tumor tissue and the age of patients. It is showed that the less hormone dependence of the tumor the higher viscosity of erythrocyte membranes that manifested by a decrease in the coefficient of eximerization (CE) of pyrene in the protein/lipid and in particular, lipid/lipid membrane layers. Increasing CE of pyrene in lipid/lipid layer of erythrocyte membranes above 1.7 units, reflecting a decline in their microviscosity, could be considered as an additional extra-tumor criterion for identification of the tumor as of hormone dependent type.