Abstract

Intraoperative portal and central venous blood samples were obtained from a total of 22 patients with colorectal cancer, and central/portal blood carcinoembryonic antigen (CEA) level ratios were compared for each stage of the disease. The percentages of patients whose central/portal blood CEA level ratio was found to be over 0.80 were 33%, 50% and 80% for stages B, C, and D respectively and the ratio of the mean CEA values were 0.32, 0.47 and 0,99 for stages B, C, and D respectively. It is concluded that this ratio is more likely to be elevated as the stage of the disease increased which might be of potential value in detecting occult metastases and predicting recurrences.