TUMOR-MARKER CA-125 IN TISSUES OF THE FEMALE REPRODUCTIVE-TRACT AND IN SERUM DURING THE NORMAL MENSTRUAL-CYCLE

Objective: To further elucidate the origin of the physiological CA-125 amounts that lead to cyclic changes in CA-125 serum levels in normall y menstruating women. Design: Fifty-three normal endometria, 13 fallop ian tubes, 25 ovaries, and nine isolated corpora lutea were prospectiv ely investigated for their CA-125 content in a sandwich solid-phase RI A and by immunohistochemistry. In addition, endometrial CA-125 tissue content was compared with the actual CA-125 serum levels of the study patients. Results: Cytosolic CA-125 concentrations were 20-fold and tw ofold higher in the endometrium than those measured in the ovary and t he fallopian tube, respectively. Moreover, only in the endometrium did CA-125 content show significant cyclic changes, with the highest conc entrations during the early proliferative and middle secretory phase. The lowest tissue concentrations were measured during the early secret ory phase. Furthermore, during the early and middle secretory phases c ytosolic CA-125 was negatively associated with CA-125 serum levels. In immunohistochemistry, marked distributional changes in OC-125 reactiv ity were revealed in the basalis and the functionalis throughout the m enstrual cycle and the postovulatory loss of CA-125 expression was fou nd to be strongly connected with early secretory transformation of gla ndular epithelium. Conclusion: Our findings indicate that the CA-125 a mounts responsible for cyclic changes in serum levels in normally mens truating women seem to be a product of normal endometrium.