[Carcinoembryonic antigen in ascites and pleural effusions]

The purpose of this prospective study was to evaluate the usefulness of carcinoembryonic antigen (CEA) assays in effusion fluids for the diagnosis of cancer. From 1978 to 1981, 63 patients totaling 67 effusions were investigated for malignant cells and CEA concentrations. There were 62 cases of ascites and 5 cases of pleural effusion resulting from 35 cirrhoses and 28 cancers, including 17 adenocarcinomas. Macroscopic examination of serous membranes was possible in 24 patients. CEA concentrations at least 4 times higher than the upper limit of normal laboratory values were required to diagnose malignancy in effusions. The specificity of both cytology and CEA assays was 100 p. 100 in cirrhotic ascites. Malignant cells were present in 14 cases and positive CEA levels in 19 cases. CEA concentrations were highly significant (p less than 0.001) of cancerous effusions due to adenocarcinomas. In cancers other than adenocarcinoma and in hepatocarcinoma, CEA assays did not prove useful, and cytological examination remained the best diagnostic method. Both cytology and CEA levels were positive for malignancy in 11 effusions, and a diagnosis of cancer could be made on these grounds in 22 out 28 cases. Lack of correlation between CEA concentrations in sera and in effusion fluids suggests local production consecutive to invasion of the serous membranes. All 8 adenocarcinoma patients with grossly detectable extension to the peritoneum had high CEA concentrations, but malignant cells were absent in 4 cases. This discrepancy might tentatively be explained by local dissemination via the lymphatic system without disruption of the membrane but resulting in reflux of CEA into the effusion fluid.(ABSTRACT TRUNCATED AT 250 WORDS)