[Carcinoembryonic antigen (CEA) and CEA-like activities in ascites and pleura-effusions (author's transl)].

Carcinoembryonic antigen (CEA) was assayed in 18 samples of non-malignant and 21 samples of malignant effusions. In 95% of benign effusion CEA activity was found within normal limits and increased only in one case of Klebsiella pneumonia. In 57% of the 21 malignant effusions CEA levels were elevated and in 4 cases elevated titers were first indications of the malignancy of the effusion. In some cases remarkable differences between serum titer and effusion titer were found. Combined measurement of CEA activity in plasma and effusion increases diagnostic value.