Steroid hormone receptors related to parameters characterizing the biology of human breast cancer.

Steroid hormone receptors are important parameters to characterize breast tumors. Thus, it is important to evaluate their relationships with factors such as histological type and size of the tumor, axillary lymph node invasion and distant spread, age and menopausal status of the patients, and parameters of tumor differentiation. The receptor levels observed vary within wide ranges. Therefore, statistically significant differences between different groups of parameters are seldom found. A significant dependence on receptor levels has been observed only for patient age and menopausal status. The parameters clinical stage, tumor size, tumor histology, metastatic involvement and histopathologic grading showed no statistically significant relation with receptor levels. Nevertheless, a relationship exists between all parameters mentioned and the frequency of a positive receptor status. Consequently, receptor status can contribute to define the biological behavior of the disease in specific groups of patients. In individual cases other parameters than the biochemical evidence of steroid receptor binding seem to be more important. We found that data derived from DNA flow cytometric measurements allowed a better recognition of tumor aggressiveness than ER status. In axillary lymph node metastases we usually observed higher receptor levels than in primary tumors, but we did not find an age dependency of ER levels in these metastases.