Hormone receptor status in human endometrial adenocarcinoma

Steroid receptor levels were determined in 196 samples of endometrial adenocarcinoma: cytosol estradiol receptors (ERc) were measured in 171 samples, cytosol progesterone receptors (PRc) in all samples; nuclear estradiol receptors (ERn) and nuclear progesterone receptors (PRn) in 68 samples; total estradiol receptors (ERt = ERc plus ERn) and total progesterone receptors (PRt = PRc plus PRn) were measured in 68 samples. The ERc levels were 88.2 +/- 8.9 (mean +/- SEM) and ERn were 94.4 +/- 15.6 fmol/mg protein; PRc levels were 197.9 +/- 25.9 and PRn 178.3 +/- 55.9 fmol/mg protein. The ERt levels were 162.6 +/- 23.2 and PRt 249.8 +/- 75.7 fmol/mg protein. The presence of PRc was related to the ERc levels according to the cut-off used. Estradiol receptors (ER) and progesterone receptors (PR) were present in the cytoplasmic and nuclear fractions in 60.2% and 36.8% of cases, respectively. The simultaneous presence of both ERt and PRt was observed only in 27.9% of cases. In the normal endometrium ERc and PRc were negatively correlated (r = -0.525, P less than 0.005), whereas in endometrial adenocarcinoma the correlation was positive (r = 0.491, P less than 0.001). In contrast with the normal endometrium the correlation between ERc and ERn was positive (r = 0.582, P less than 0.001) in tumor tissue. In neoplastic tissue Scatchard analysis showed a single class of specific ERc sites with a dissociation constant (Kd) of 1.39 +/- 0.8 X 10(-9) mol/l, one tenth of that found in the normal premenopausal endometrium. Qualitative and quantitative analysis of the receptor status showed that in 30% to 40% of cases studied the behavior of the neoplastic cell was similar to that found in the normal endometrial cell. In a 4-year follow-up of patients affected by endometrial adenocarcinoma there is better survival in the groups of patients with a simultaneous presence of ERt and PRt than in the group with their absence.