Please use this identifier to cite or link to this item: http://hdl.handle.net/1946/20633
Estrogen receptors (ER) in 182 human breast cancer samples and progesterone receptors (PR) in 160 samples were measured with the dextran-coated charcoal (DCC) method. An inter-laboratory investigation was carried out on 10 samples and the results were in good agreement (r=0,997 for ER and r= 0,971 for PR). Of the 154 primary cancers 73% were ER+, of the 135 primary cancers in which both receptors were measured, 55% were ER+PR+, 15% were ER+PR-, 26% were ER-PR- and 4% were ER-PR+. Of the 28 samples of metastatic breast cancer 61% were ER+. Of the 25 samples in which both receptors were measured, 40% were ER+PR+, 24% were ER+PR-, 36% were ER-PR- and 0% were ER-PR+. Thus relatively fewer samples from metastatic cancer contain receptors, which indicates that receptor-negative cells more easily form metastatic growth. The receptor status in the primary breast cancer samples was correlated with the menopausal stage of the patient. The premenopausal patients showed higher proportion of positive results while having lower receptor content that the postmenopausal group. This might indicate some difference in oncogenesis between premenopausal and postmenopausal breast cancer. Receptor status in sampels taken as biopsy specimens (103) was compared to those taken as mastectomy specimens (51 samples). The results show reduced number of positive (ER+ and PR+) samples in the mastectomy samples compared with the biopsy samples, especially in the low positive group (<50 fmol/mg). The number of samples containing only one type of receptor (ER+PR- or ER-PR+) was higher in the mastectomy samples than the biopsy samples. This indicates that there is more autolytic loss of receptors in the mastectomy specimens due to insatisfactory cooling and breakdown of receptors during the mastectomy operation. A tumor with a low level of ER and/or PR might yield a false negative result in a mastectomy specimen.