A comparative study of serum alpha-beta A immunoreactive inhibin and tumor-associated antigens CA125 and CEA in ovarian cancer.

alpha-i.r Inhibin, has been recently proposed as a useful tumor marker for mucinous ovarian carcinomas (Ca), as the widely used tumor marker for ovarian malignancies, CA125 is efficient only in nonmucinous ovarian Ca, and, together with CEA, fails to detect minimal disease and show long half-life in serum after successful surgery. Moreover, conflicting evidence has been reported as to whether inhibin in ovarian malignancies is the biologically active dimer alpha-beta A inhibin or the inactive free alpha-subunits and inhibin precursors. Serum alpha-beta A i.r inhibin. CA125 and CEA were measured preoperatively and 8 days postoperatively in 39 postmenopausal patients with ovarian cancer (13 mucinous, 15 serous and 11 different other ovarian Ca) in comparison with 20 age-matched healthy women (Controls), 18 patients with benign ovarian tumors and 10 patients with nonovarian gynecological malignancies. Serum alpha-beta A i.r inhibin values were very low in controls (0.121 U/ml; 0.060-0.250) while they were greatly elevated in both benign (67% sensitivity) and malignant ovarian tumors (100% sensitivity in mucinous Ca, 80% in serous and 90.9% in other ovarian Ca, taken as cut-off level the maximum value in Controls, 0.250 U/ml). In contrast, in non-ovarian malignancies no increased values of alpha-beta A inhibin were found (0% sensitivity). Our results on the sensitivity of CA125 and CEA are in agreement with previous studies. After successful surgery the very high concentrations of alpha-beta A i.r. inhibin were reduced very rapidly (8 days) to normal postmenopausal values in contrast to those of CA125 and CEA, that remained elevated. Serum alpha-beta A i.r inhibin seems to be very useful in monitoring after treatment the patients with any type of ovarian malignancy and specifically those with mucinous ovarian cancer.