Diagnostic value of carcinoembryonic antigen in malignancy-related ascites : systematic review and meta-analysis

Background and study aims : There is a common misconception that malignant ascites is equivalent to peritoneal carcinomatosis. It seems that malignancy-related ascites is a more appropriate -description- of- malignant- ascites,- which- is- difficult- to- confirm. Carcinoembryonic antigen, a glycoprotein tumor marker shed by malignant cells, increases in a wide range of gastrointestinal malig- nancies. We carried out the current meta-analysis to determine carcinoembryonic antigen accuracy in the diagnosis of malignancy- related ascites. Patients and methods: Pudmed/Medline and SCOPUS were searched using these search terms : malignan* AND ascites AND (CEA OR carcinoembryonic). The outcome of interest was carcino- embryonic antigen accuracy in the differentiation of malignancy- related ascites and nonmalignant ascites. Results : Seven studies were included in this systematic review. Pooled diagnostic indices using random-effects model were as fol- lows-:- sensitivity- 43.1%- [381-48.3]-;- specificity- 95.5%- [93-97.3]-; LR+- (positive- likelihood- ratio)- 7.33- [4.58-11.73]-;- LR-- (negative likelihood- ratio)- 0.6- [0.54-0.68]-;- and- DOR- (diagnostic- odds- ratio) 12.93-[7.58-22].- Conclusions :-Carcinoembryonic-antigen-of-the-ascitic-fluid-does not seem to be sensitive enough to diagnose malignancy-related -ascites.- However,- due- to- high- specificity,- the- positive- predictive value of this marker is high and the higher the level of carcino- embryonic antigen, the more likely it is to be malignancy-related. Nevertheless,- a- negative- test- result- cannot- definitely- rule- out- the malignancy. (Acta gastroenterol. belg., 2014, 77, 418-424).