Erythropoietin Is Detectable in the Ascitic Fluid in Patients With Ovarian Tumors

Abstract

Erythropoietin (Epo) is a glycoprotein that stimulates proliferation and migration of human endothelial cells and promotes angiogenesis, which are crucial phenomena in cancer biology. The objective of this study was to investigate whether Epo is detectable in the ascitic fluid of patients with ovarian tumors. We investigated the presence of Epo in the ascitic fluid of 100 women undergoing laparotomy for an ovarian tumor. Epo concentration was quantitated with an immunochemiluminometric assay. Ten women had a benign tumor, 13 women had a borderline tumor, and 77 women had ovarian cancer. Epo was detected in all ascitic fluid samples, in similar amounts as in corresponding serum samples. Ascitic fluid Epo concentration did not differ between the 3 study groups (P = 0.081), but in multiple comparisons, ascitic fluid Epo was higher in the women with cancer than in the women with a benign tumor (P = 0.006). Ascitic fluid Epo concentration correlated positively with serum Epo (P < 0.0001) and the volume of ascites (P < 0.0001). In regression analyses, serum Epo, volume of ascites, blood hemoglobin, plasma CA125, tumor stage, tumor grade, and the presence of residual tumor after surgery had no significant independent effect on ascitic fluid Epo. Considerable amounts of Epo are present in the ascitic fluid of women with ovarian tumors. The origin of Epo in the ascitic fluid of women with ovarian tumors as well as the clinical relevance of our finding remain to be clarified.