title: Diagnostic usefulness of carbohydrate antigen-125 in cancerous and noncancerous peritoneal effusions.
abstract: Carbohydrate antigen-125 (CA-125) is a tumor marker that has been used for differential diagnosis of peritoneal malignancies. The aim of the present study was to evaluate the diagnostic usefulness of simultaneous quantification of CA-125 in peritoneal fluid and serum for abdominal cancer cases and noncancer diseases. Noncancer disease group included cirrhotic patients (n=28) and spontaneous bacterial peritonitis (SBP) patients (n=11). Abdominal cancer group was composed of histologically diagnosed various malignancies (n=10), such as gastric cancer. CA-125 levels were quantified by chemiluminescent enzyme immuno-assay. Diagnostic usefulness tests and receiver operating characteristics (ROC) curve analysis were performed for the levels of peritoneal fluid CA-125 (pCA-125) and serum CA-125 (sCA-125), and the ratio of pCA-125 to sCA-125 (p/sCA-125). The sCA-125 levels were significantly higher in noncancer patients than those in the cancer patients, while the pCA-125 levels showed no significant difference between the two groups. Notably, the p/sCA-125 ratio was significantly lower in the noncancer patients than that in the cancer patients. Area under the ROC curve was 0.267 for sCA-125, 0.542 for pCA-125 and 0.831 for p/sCA-125. The accepted cutoff values were the combination of values that gave the greatest diagnostic sensitivity plus specificity. Either sCA-125 or pCA-125 value gave lower diagnostic accuracy, whereas p/sCA-125 value demonstrated a significantly higher diagnostic accuracy (sensitivity-specificity pairs: 0.40-0.33 for sCA-125, 0.60-0.54 for pCA-125, and 0.80-0.72 for p/sCA-125, respectively). Hence, determination of p/sCA-125 improves the biochemical discrimination of abdominal cancerous cases from noncancerous diseases.
authors.affiliation: Department of Internal Medicine, Dokuz Eylul University School of Medicine, Izmir, Turkey.
authors.forename: Türker
authors.initials: T
authors.lastname: Kemer
authors.forename: Murat
authors.initials: M
authors.lastname: Ormen
authors.forename: Filiz
authors.initials: F
authors.lastname: Kuralay
authors.forename: Mustafa
authors.initials: M
authors.lastname: Pehlivan
authors.forename: Belkis
authors.initials: B
authors.lastname: Unsal
authors.forename: Ethem
authors.initials: E
authors.lastname: Tankurt
mesh_terms: D001202:Ascitic Fluid / Q000276:immunology*; D018394:CA-125 Antigen / Q000097:blood / Q000276:immunology; D005355:Fibrosis / Q000276:immunology; D006801:Humans; D009369:Neoplasms / Q000175:diagnosis* / Q000276:immunology; D010538:Peritonitis / Q000276:immunology; D012372:ROC Curve
chemical_list: D018394:CA-125 Antigen