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Carcinoembryonic antigen elevation in post-hepatectomy patients with colorectal cancer liver metastasis indicates recurrence with high accuracy.

BACKGROUND/AIMS
We aimed to retrospectively determine the accuracy of postoperative serum carcinoembryonic antigen (CEA) monitoring to detect or rule out recurrence in post-hepatectomy colorectal cancer patients by using a new statistical technique, likelihood ratio and post-test probability.


METHODS
A total of 110 colorectal cancer patients who underwent curative hepatectomy were enrolled. A serum CEA assay and radiological examination were performed routinely for 5 years after surgery or until recurrence was detected. Yearly recurrence rates, sensitivities, specificities, and likelihood ratios were calculated. Post-test probabilities were calculated using these values.


RESULTS
All episodes of recurrence occurred within 3 years after hepatectomy. The most frequent recurrence site was the liver, with a recurrence rate of 61.4% of all recurrence. The post-test probabilities of recurrence in post-hepatectomy colorectal cancer patients with positive and negative serum CEA were approximately 70-90% and 10%, respectively.


CONCLUSIONS
CEA elevation in colorectal cancer patients who underwent curative resection indicated recurrence with high accuracy because of the high recurrence rate in the liver, in which CEA elevation is more frequent than in other recurrent sites. The elevation of CEA in post-hepatectomy patients necessitates frequent examination using imaging techniques to reveal undetected metastasis as soon as possible.