Carcinoembryonic antigen gradients between plasma and malignant ascites: use in detecting peritoneal and liver metastases.

In the study of 19 patients with malignant ascites and elevated plasma carcinoembryonic antigen (CEA) (greater than 2.5 ng/ml) and/or ascites CEA (greater than 10 ng/ml), two patients emerged: 1) The 10 patients with higher ascitic fluid than plasma CEA levels (medians: 230 and 10.6 ng/ml, respectively) had exudates and intraperitoneal cancer but usually had no hepatic metastases.

The disparity of indirect and direct zirconyl-gel assays for carcinoembryonic antigen.

Experience with the zirconyl phosphate gel (Z-gel) radioimmunoassays for plasma CEA levels below 20 ng/ml (the indirect method) and for levels greater than 20 ng/ml (the direct method) has shown that a disparity of values exists, caused by shifting from one assay to the other. This disparity is at least partially due to PCA-labile proteins reacting in the direct assay. It may be constant for individual patients but varies among patients.

Transient carcinoembryonic antigen (CEA) elevations following resection of colorectal cancer: a limitation in the use of serial CEA levels as an indicator for second-look surgery.

In a previous study, other investigators recommended second-look surgery for colorectal cancer primarily on the basis of plasma carcinoembryonic antigen (CEA) rises and prepared a nomogram for ready recognition of these "significant" increases. We found 25 patients whose CEA levels met the recommended criteria for significance; however, in 9 of these patients the rises were transient. Eight had no clinical evidence of recurrent cancer and they might have had negative second-look surgery had this been done because of CEA rises alone.

Circulating immune complexes in patients following clinically curative resection of colorectal cancer.

Sixty-nine patients have been followed prospectively after curative resection of Dukes-Kirklin B-2 or C colorectal cancer. Serial plasma samples were studied in selected patients to determine changes in circulating immune complex concentrations (CIC) following primary tumor resection, and to compare serial plasma CIC and carcinoembryonic antigen (CEA) levels. CIC was determined in an average of seven serial samples per patient by inhibition of antibody-dependent cell-mediated cytotoxicity (ADCC).