Prognostic significance of CEA levels and detection of CEA mRNA in draining venous blood in patients with colorectal cancer.

ABSTRACT

BACKGROUND AND OBJECTIVES: The aims of this study were to determine carcinoembryonic antigen (CEA) levels and incidence of tumor cells using the RT-PCR technique in draining venous blood of patients with colorectal cancer, correlate the results with various histopathologic factors and determine their significance as prognostic factors. METHODS: From 1995 to 2000, 108 patients with adenocarcinoma of the colon or rectum, underwent curative surgery and enrolled in this prospective study. RESULTS: The 5-year survival group had significantly lower portal CEA levels compared to the hepatic metastasis outcome group. CEA mRNA was positive in the draining venous blood from 12 (11.1%) out of 108 patients included in the study. The rate of positive tumor cell detection in portal blood was significantly higher in the hepatic metastasis outcome group than in the 5-year survival and recurrence group. The proportion of patients with portal CEA > or =5 ng/ml was greater in patients with higher stage than in patients with lower stage. CONCLUSIONS: Positive CEA mRNA in draining venous blood predicted hepatic metastases and local recurrence with accuracy over 80% but with low sensitivity of 30% and 9%, respectively. Moreover, CEA level was a sensitive indicator in hepatic metastases as sensitivity was 95% and a specific indicator in predicting 5-year survival with specificity 84%.