Colorectal cancer patients with high risk of hematogenous metastasis: Correlation with CEA levels in peripheral and draining venous blood during the period of operation

Correlations between carcinoembryonic antigen (CEA) levels of peripheral (p) and draining (d) venous blood during the period of operation, and pre- and post-operatively detected hematogenous metastases were examined in 78 patients with colorectal cancer. The metastases were found in 28 patients (HM group), but not found in the other 50 patients (non-HM group). The mean values (43 and 198 ng/ml) and positive rates (61 and 96%) greater than 5 ng/ml of p- and d-CEA levels in the HM group were significantly higher than those (6 and 14 ng/ml, and 22 and 48%, respectively) in the non-HM group. The differences (mean 184 ng/ml and positive rate 49%) of d-CEA levels between both groups were more significant than those (39 ng/ml and 30%) of p-CEA levels. The mean value (155 ng/ml) and positive rate (82%) greater than 5 ng/ml of the gradient between d- and p-CEA levels (d-p CEA gradient) in the HM group were significantly higher than those (8 ng/ml and 34%) in the non-HM group. These results suggest that patients with a high risk of hematogenous metastases are more effectively checked by the determination of d-CEA levels and d-p CEA gradient than of p-CEA levels, and that they are patients with positive d-CEA and d-p CEA gradient levels.