Purpose: Carcinoembryonic antigen (CEA) has limited value as an isolated predictor for survival among colorectal cancer (CRC) patients. D-dimer (DD) is a strong predictor of survival among metastatic CRC patients, but the prognostic value in non-metastatic CRC patients remains controversial. We examined the prognostic value of preoperative DD levels in relation to CEA levels in non-metastatic, resectable CRC patients.
Methods: Between October 2003 and November 2005, 166 patients were included. We used the Kaplan-Meier method to compute 5-year mortality rates, stratified by preoperative DD and CEA levels. Adjusted Cox regression analysis was used to compute mortality rate ratios (MRRs) during postoperative years 0-1 and 1-5 based on the preoperative CEA and DD levels.
Results: The cumulative 5-year mortality rate was 15 % (95 % confidence interval [CI], 9-25 %) in patients with normal DD and CEA levels, 30 % (CI, 16-53 %) in patients with isolated elevated CEA levels, 37 % (CI, 25-53 %) in patients with isolated elevated DD levels, and 60 % (CI, 37-83 %) in patients with elevated CEA and DD levels. Elevated CEA was associated with an approximately ten-fold increase in mortality within the first postoperative year (adjusted MRR 9.8, CI 2.5-38.3); this association was lost during postoperative years 1-5 (adjusted MRR 1.1, CI 0.5-2.7). Elevated DD was associated with a greater than two-fold increase in mortality during postoperative years 0-1 (adjusted MRR 2.8, CI 0.7-11.0) and 1-5 (adjusted MRR 2.2, CI 1.1-4.8).
Conclusion: DD is a strong predictor of survival among non-metastatic curatively resected CRC patients, particularly in combination with CEA.