Preoperative Carcinoembryonic Antigen as a Poor Prognostic Factor in Stage I-III Colorectal Cancer After Curative-Intent Resection: A Propensity Score Matching Analysis

Background. Preoperative carcinoembryonic antigen (CEA) has yet to be used as a prognostic or adjuvant chemotherapy factor for colorectal cancer (CRC). Methods. This retrospective cohort study included all stage I-III CRC patients with different preoperative serum CEA levels (B 5, 5-10, and[10 ng/ml) at a single center between 1995 and 2010. Propensity score matching was performed in a 1:1 ratio between the two elevated CEA groups (5-10 ng/ml and[10 ng/ml) and in a 1:2 ratio between the elevated and non-elevated groups (B 5 ng/ml), with a caliper of 0.05. Results. After exclusion and matching, 3857 patients had preoperative CEA levels B 5 ng/ml, 1121 patients had CEA levels between 5 and 10 ng/ml, and 1121 patients had CEA levels[10 ng/ml. Elevated preoperative CEA showed an increased risk of overall survival (5-10 ng/ml: hazard ratio [HR] 1.376;[10 ng/ml: HR 1.523; both p\0.001), cancer-specific survival (5-10 ng/ml: HR 1.404;[10 ng/ml: HR 1.712; both p\0.001), and recurrence free interval (5-10 ng/ml: HR 1.190;[10 ng/ ml: HR 1.468; both p\0.05). Patients with negative lymph node staging (LNs) and CEA[10 ng/ml, as well as those with positive LNs and CEA B 5 ng/ml, showed similar overall survival (5-year survival: 72% vs. 69%; p = 0.542) and recurrence free intervals (19.9 vs. 21.72 months; p = 0.662). Conclusions. A preoperative CEA level can be an independent prognostic factor for stage I-III CRC after curative resection. Patients with negative LNs and preoperative CEA level[10 ng/ml should be considered for intensive follow-up or adjuvant chemotherapy.