Correlation between estradiol-17 beta and progesterone cytosol receptor concentration, histologic differentiation and 3H-thymidine incorporation in endometrial carcinoma.

Women treated with estrogen exhibit a higher risk of developing endometrial cancer. steroid hormones exert their effects on target tissue through specific cytosol receptor protein. Knowledge of this steroid receptor concentration in endometrial carcinoma might facilitate the treatment of recurrences. We have compared the concentrations of endometrial estrogen and progesterone cytosol receptors with the histologic grade of endometrial carcinoma as well as the rate of 3H-thymidine incorporation. We found a significant difference in receptor concentration between well-moderately differentiated tumours and poorly differentiated ones. No correlation was found between 3H-thymidine incorporation rate and differentiation. A positive correlation between thymidine incorporation rate and progesterone receptor concentration was noticed. The concentration of receptors varies within a wide range of each group of differentiation; thus 23% and 4% of the poorly differentiated tumours had higher concentration of estradiol and progesterone receptors respectively than the median values for well differentiated tumours.