SERIAL SERUM CA-125 MEASUREMENTS FOR EVALUATION OF RECURRENCE IN PATIENTS WITH ENDOMETRIAL CARCINOMA

Objective: To evaluate the usefulness of serum assays for CA 125 to de tect recurrent endometrial carcinoma. Methods: Two hundred sixty-six p atients were studied with 1101 post-treatment assays. Patients were ca tegorized as low, medium, or high risk based on surgical-pathologic fi ndings. CA 125 values were analyzed with respect to each patient's dis ease status. Results: Serial CA 125 levels were elevated (greater than 35 U/mL) in 19 of 33 patients (58%) with recurrent disease. Among 236 surgically treated patients, 97 (41.1%), 42 (17.8%), and 97 (41.1%) w ere considered low, medium, and high risk, respectively. None of the l ow-risk and only two (4.7%) of the medium-risk patients developed recu rrent disease. One of the latter patients was detected based on an ele vated CA 125 level alone. Twenty-seven (27.8%) of the high-risk patien ts developed recurrent disease, 23 of whom had elevated pre-treatment CA 125. Fifteen of 16 (94%) with recurrent disease had an elevated CA 125 level. Nine of 12 patients with papillary serous carcinoma experie nced recurrence; eight of these nine had elevated CA 125 levels at dia gnosis and recurrence, in contrast to only one patient with a normal p re-treatment level (P =.018). False elevations were noted in 13 patien ts, 12 of whom had received radiation therapy. Conclusions: CA 125, if elevated at diagnosis of endometrial carcinoma, is an important marke r for recurrent disease. The use of serial CA 125 assays is most benef icial in diagnosing recurrence in a high-risk population, including pa tients with papillary serous carcinomas. False elevations may occur fo llowing radiation therapy.