Differential Diagnosis between Uterine Myoma and Endometriosis using CA 125 as a New Tumor Marker of Ovarian Carcinoma

Abstract

Abstract For a preoperative differentiation between leiomyomata uteri and adenomyosis, we measured serum levels of the antigen CA 125, which is specific to ovarian non‐mucinous epithelial carcinoma, in patients with benign gynecologic diseases (39 leiomyomata uteri, 10 adenomyosis, 4 adenomyosis with leiomyomata uteri, 3 adenomyosis with external endometriosis and 4 external endometriosis). Using radio‐immunoassay (RIA) kit, we found the normal range of CA 125 levels to be below 34 U/ml. The mean CA 125 level (±S.D.) was 20.3 ± 10.3 U/ml in patients with leiomyomata uteri and 151.2 ± 157.3 U/ml in those with adenomyosis. The mean CA 125 level in patients with leiomyomata uteri was not statistically higher than that in disease‐free women. The mean CA 125 level in patients with adenomyosis was statistically higher than that in disease‐free women. Of 17 patients with surgically demonstrable adenomyosis, the CA 125 values were over 34 U/ml in 16 (94.1%). Three (75%) of 4 patients with surgically demonstrable external endometriosis had a serum CA 125 level in excess of 34 U/ml. Of 39 patients with surgically demonstrable leiomyomata uteri, CA 125 levels were below 34 U/ml in 37 (94%). CA 125 levels in patients with adenomyosis gradually decreased postoperatively and all were below 34 U/ml within four weeks. Using this approach, leiomyomata uteri and adenomyosis can be differentiated preoperatively and the response to treatment in patients with endometriosis can be monitored.