The serum level of carcinoembryonic antigen in drainage venous blood is not a sensitive predictor of metachronous hepatic metastasis for patients with colorectal cancer

Risk Stratification Based on Synchronous Neoplasia and Clinical Physicochemical Characteristics Predicts a Higher Incidence of Metachronous Advanced Neoplasia in Patients Undergoing Colorectal Resection for Colorectal Cancer

Purpose

Patients who undergo primary colorectal cancer (CRC) resection remain at increased risk for metachronous advanced neoplasia (MAN) in the remnant colorectum. This study aimed to investigate the incidence and clinicopathological characteristics predictive of MAN development in the residual colon after surgery.

Patients and Methods

We retrospectively reviewed 450 primary CRC cases referred to our hospital during a 4-year period. Univariate and multivariate analyses were performed to identify risk factors for MAN. The cumulative incidence of MAN was evaluated by the Cox proportional hazards model.

Results

MAN development was confirmed in 78 of the 450 patients (17.3%). Overall 1-, 2-, 3-, and 5-year cumulative probabilities were 0.9%, 4.8%, 9.8%, and 16.1%, respectively, for MAN. Among the clinical and colonoscopic factors at baseline, the independent factors that were significantly associated with MAN were synchronous neoplasia, carcinoembryonic antigen (CEA) level ≥10.0 ng/mL, and index cancer size ≥50 mm. The cumulative probability of MAN was significantly higher for patients with synchronous advanced neoplasia (SAN) than for those without synchronous neoplasia (P = 0.000). A subgroup analysis of patients based on the CEA level and index cancer size indicated that CEA ≥10 ng/mL and index cancer ≥50 mm resulted in a significantly higher cumulative probability of MAN (P = 0.039).

Conclusion

Patients with SAN or high preoperative serum CEA levels and large index cancer are at increased risk for early-onset MAN. More intensive surveillance strategies may be appropriate for these groups. Risk stratification based on synchronous neoplasia and clinical physicochemical characteristics requires further investigations involving modified appropriate postoperative colonoscopic surveillance schedules.

Circulating antibodies to carcinoembryonic antigen related to improved recurrence-free survival of patients with colorectal carcinoma

This prospective study evaluated the prognostic value of antibodies to carcinoembryonic antigen (anti-CEA), detected by indirect immunosorbent assay, in the serum of colorectal carcinoma patients. Serum carcinoembryonic antigen (CEA) concentrations, measured by electrochemiluminescence immunoassay, were elevated in 26 (37.7%) of 69 patients with colorectal cancer and could not be detected among the 28 patients with benign intestinal conditions or 37 healthy individuals who comprised the control groups. Anti-CEA immuno globulin (Ig)G or IgM was detected by immunonephelometry in 44 (63.8%) patients with colorectal cancer, three (10.7%) with benign intestinal conditions and four (10.8%) healthy blood donors. Differences in antibody detection frequencies between the cancer patient group and the control groups were statistically significant. Titres of anti-CEA correlated significantly with CEA levels and Dukes' cancer stage. Antibody titre was an independent, significant, favourable predictor for 5-year recurrence-free survival. It is concluded that measurement of serum anti-CEA combined with CEA might be useful as a tumour marker and to assess prognosis. These results need to be confirmed in large, well-controlled, randomized clinical trials.