Enzyme-Linked ImmunosorbentAssay of CA-i 25 in Serum of Patientswith Endometriosis: Efficacyin Diagnosis

We used an enzyme-linked immunosorbent assay to quantify CA-i 25, a cancer antigen, in serum of patients with endome-tnosis. Concentrations of CA-i 25 in 103 patients with un-treated endometriosis significantly (P <0.005) exceeded those for 31 controls with no evidence of disease: 9.1 (SD 12.3) vs 2.2 (SD 3.2) arb. units/mL. Values for patients with treated endometriosis were lower (2.3, SD 2.6, arb. units/mL, n = 9) than those for patients with untreated endometnosis. The mean concentrations of CA-i 25 in different stages of untreated endometriosis were 4.8 (SD 4.5), 7.1 (SD 9.9), 9.8 (SD 13.2), and 10.8 (SD 13.0) arb. units/mL for Stages I, II, III, and IV, respectively. The differences between controls and each stage were statistically significant (for all stages: P <0.05). We also assayed serum sampled from controls and patients with untreated endometnosis during menstruation