Steroid receptors and the distribution of IR-carcinoembryonic antigen in colonic cancer.

Twenty-five colonic cancer tissues were studied for the presence of estrogen and progesterone receptors (ER, PR) and the distribution of immunoreactive carcinoembryonic antigen (IR-CEA). ER and PR were determined in 6 (24 per cent) and 3 (12 per cent), respectively, of 25 patients with colonic cancer. Of the six patients with ER, five were females, four of whom were postmenopausal. Steroid receptors, however, had no correlation with age, tumor localization, stage of disease or IR-CEA. In cancer tissue, IR-CEA in the cytosol fraction was higher than that found in the membrane fraction. In normal colon, however, the concentrations of the two fractions were reversed. Immunohistochemical findings have shown a different distribution of IR-CEA in cancerous and normal colon, and our results demonstrated similar findings by using radioimmunoassay (RIA).