title: Serum and peritoneal fluid CA-125 levels in patients with endometriosis.
abstract: OBJECTIVE
  To evaluate CA-125 in peritoneal fluid (PF) as an indicator of endometriosis.
  
  
  METHODS
  CA-125 levels in paired serum and PF were determined by the one-step immunoradiometric assay. For peritoneal samples, high dilution of the sample (1:100) was used to avoid false low results, caused by the "hook effect" phenomenon.
  
  
  METHODS
  Forty-one women with and without endometriosis, undergoing laparoscopy or laparotomy during the follicular phase of the menstrual cycle, were selected.
  
  
  METHODS
  2nd Institute of Obstetrics and Gynecology, University of Rome "La Sapienza," Rome, Italy.
  
  
  METHODS
  Peritoneal fluid CA-125 levels obtained using diluted samples were significantly higher than those found using undiluted ones.
  
  
  RESULTS
  CA-125 levels in PF were approximately 100 times higher than those found in paired serum, ranging from 970 to 10,636 U/mL. In patients with endometriosis, CA-125 levels in PF were significantly elevated when compared with the control group. In serum, CA-125 levels increased only in advanced stages of endometriosis.
  
  
  CONCLUSIONS
  The sensitivity of the CA-125 test for endometriosis in PF is greater than in serum. Therefore, the measurement of CA-125 levels in PF could be useful in the detection of early stage endometriosis, which tends to be overlooked by the CA-125 serum test.
authors.affiliation: 2nd Institute of Obstetrics and Gynecology, University of Rome, La Sapienza, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Barbati
authors.forename: E V
authors.initials: EV
authors.lastname: Cosmi
authors.forename: R
authors.initials: R
authors.lastname: Spaziani
authors.forename: R
authors.initials: R
authors.lastname: Ventura
authors.forename: G
authors.initials: G
authors.lastname: Montanino
mesh_terms: D000293:Adolescent; D000328:Adult; D015295:Antigens, Tumor-Associated, Carbohydrate / Q000097:blood* / Q000378:metabolism*; D001202:Ascitic Fluid / Q000378:metabolism*; D004715:Endometriosis / Q000378:metabolism*; D005260:Female; D006801:Humans; D015592:Immunoradiometric Assay; D008875:Middle Aged; D012016:Reference Values
chemical_list: D015295:Antigens, Tumor-Associated, Carbohydrate