Association of steroid hormone receptor content and flow cytometric DNA ploidy in endometrial carcinoma.

Flow cytometric DNA ploidy and sex steroid hormone receptor activity was measured in 55 endometrial carcinomas. DNA ploidy was measured on paraffin-embedded specimens and ER and PR activity was measured using both biochemical and immunohistochemical assay. Association of these parameters was tested using logistic regression model. Diploid or near diploid DNA histogram was seen in 40 cases (72.7%). All Grade 1 tumours (n = 15) were diploid whereas 38.5% of Grade 2 (n = 27) and Grade 3 (n = 13) tumours were aneuploid (grade 1 vs Grade 2 and 3, P = 0.0031). The mean value of ER was 109 +/- 120 (SD) fmol/mg protein for diploid tumours and 48 +/- 50 fmol/mg protein for aneuploid tumours (P = 0.0093). The corresponding values for PR were 226 +/- 262 fmol/mg protein and 75 +/- 102 fmol/mg protein (P = 0.0073), respectively. In immunohistochemical assay the mean HSCORE of ER was 45 +/- 77 for diploid tumours and 27 +/- 48 for aneuploid tumours (P = 0.43). The corresponding values for PR were 32 +/- 55 and 22 +/- 56, respectively (P = 0.58). In logistic regression analysis cytosolic PR content was associated with DNA ploidy.