DETERMINATION OF A NORMAL LEVEL OF SERUM CA125 IN POSTMENOPAUSAL WOMEN AS A TOOL FOR PREOPERATIVE EVALUATION AND POSTOPERATIVE SURVEILLANCEOF ENDOMETRIAL CARCINOMA

In an attempt to determine a normal level of CA125 in postmenopausal w omen, CA125 levels of normal postmenopausal women (n = 36, 58.2 +/- 8. 1 years) and postmenopausal women undergoing hormone replacement thera py (HRT) (n = 111, 56.8 +/- 6.1 years) were studied. A mean CA125 conc entration of 10.0 +/- 3.8 U/ml was found in postmenopausal women witho ut HRT and was significantly lower than that of postmenopausal women u ndergoing HRT (12.8 +/- 3.8 U/ml), indicating that the cutoff level of CA125 in postmenopausal women or women without reproductive organs sh ould be estimated at a level lower than that conventionally accepted. A receiver operating characteristic (ROC) curve for a preoperative eva luation of myometrial invasion was analyzed in postmenopausal women wi th endometrial cancer (n = 110). A novel cutoff level of 20 U/ml of CA 125 could detect myometrial invasion to more than one-half of the myom etrium with sensitivity of 69.0%, specificity of 74.1%, positive predi ctive value of 58.8%, and negative predictive value of 81.6%. In addit ion, the distribution of CA125 levels was analyzed in patients who had undergone an operation for endometrial cancer more than 2 years earli er and as yet had no clinical evidence of recurrence of the disease. N inety-six point two percent of 619 measurement values were lower than 20 U/ml. These results suggest that the novel CA125 level of 20 U/ml i s clinically useful for preoperative evaluation and postoperative surv eillance of endometrial carcinoma. (C) 1998 Academic Press.