Differences in Tumor Growth Measured by Carcinoembryonic Antigen Doubling Time between Synchronous and Metachronous Hepatic Colorectal Metastases

Abstract

The operative results and carcinoembryonic antigen (CEA) doubling times of patients with synchronous hepatic metastasis (group A) and metachronous hepatic metastasis (group B) from colorectal carcinoma were compared. Better survival was exhibited in group A and group B patients who underwent hepatic resection than in those who did not undergo hepatic resection. Group B patients with resectable metastasis also exhibited longer survival times compared to patients with similar CEA doubling times and without hepatic resection. Among the patients who did not undergo hepatic resection, group B showed better survival times than group A after colorectal resection, and the CEA doubling time obtained from 6 patients in group B (83 ± 22 days) was significantly longer than that obtained from 10 patients in group A (55 ± 19 days). The CEA doubling time correlated well with the survival time in unresectable group B patients. The better survival of group B patients may be due not only to the delay in detection of hepatic metastasis but also to the slower growth kinetics of the tumor per se, which were suggested by a longer CEA doubling time.