Abstract

A simple and inexpensive immunocytochemical technique has been used to demonstrate estrogen (EB) and progesterone binding sites (PB) in endometrial carcinoma. Tumors were considered as being ‘binding-site’ rich if more than 40% of the component epithelial cells were positive for hormone binding sites (HB). By this criterion, over half of the adenocarcinomas studied were HB rich. Significantly higher 5- and 10-year survival rates were found in women whose tumors were HB rich compared with those whose neoplasms were HB poor, and a similar trend was established for patients with a combined EB rich/PB rich status versus that of EB poor/EB poor. This beneficial effect of a rich Type I and Type II receptor site status on survival, however, was shown only to a limited extent for EB. These results were independent of adjuvant treatment and of all clinical and histopathological features of known prognostic importance, save tumor differentiation. It is concluded that the immunocytochemical determination of HB status in formalin-fixed paraffin-embedded tissues adds significantly to the prognostic information available for endometrial adenocarcinoma.