Oestrogen and progestin receptors as prognostic indicators in endometrial cancer. A review of the literature.

The history of research on oestrogen and progestin receptors in endometrial cancer goes back about 20 years. Summarized data from several clinical studies demonstrate that cytosol oestrogen (ERC) and progestin receptors (PRC) are clinically useful indicators of prognosis. Absence of receptor or its low concentration is indicative of an increased risk of recurrent malignancy. In this respect PRC tends to be more sensitive than ERC. In some studies PRC assay appeared to be more strongly correlated to prognosis than any of the conventional clinico-pathological parameters. In addition, the information obtained by ERC and/or PRC assay is independent of and additional to the classical prognostic indicators. The value of ERC and PRC assay in predicting the sensitivity of endometrial cancer to progestin therapy is of clinical interest. The accumulated data for many clinical trials show that in detecting the non-responders to progestin therapy negative results of ERC and PRC give similar information with an accuracy of about 90%. In identifying responders to progestin therapy, a positive PRC result appeared to give more precise information than a positive ERC, the accuracy being about 75% for PRC. The use of the combination of ERC and PRC determination as a prognostic indicator or predictor of sensitivity to progestin therapy does not significantly increase the information available by PRC measurement alone. Hence, whatever used--a biochemical ligand binding technique or immunohistochemical staining--PRC determination alone seems recommendable for clinical purposes.