The role of preoperative CEA in the management of colorectal cancer: A cohort study from two cancer centres.

Background: The primary aim of this study was to investigate whether a preoperative elevation in serum CEA is an independent prognostic factor for both 5-year overall and disease-free survival within an Australian patient cohort.

Materials And Methods: A retrospective study of a prospectively maintained colorectal neoplasia database for patients between January 2010 and June 2016 was performed. Patients were categorized into two groups according to the preoperative serum CEA level: low (<2.5), high CEA (≥2.5), and elevated (≥5 ng/ml); and further stratified by disease stage. Inclusion criteria were patients having had a resection for either a colonic or upper third rectal adenocarcinoma and with a preoperative CEA value. Data on patient demographics, mortality, and morbidity and survival were compiled. Five-year estimates of overall (OS) and disease-free survival (DFS) were assessed.

Results: 623 patients met the inclusion criteria. The median patient age was 73 (range 22-97) and 55% female (n = 340). There were 572 colonic cancers and 51 rectal cancers. The median follow-up time was 25 months (range 1-71). Eight patients (1%) had a local recurrence and 62 patients (10%) had evidence of metastatic disease after the initial curative resection. The 5-year OS and DFS rates for patients with CEA level <2.5 ng/ml were 85% and 86% respectively, which were higher than those with CEA level ≥2.5 ng/ml (73% and 79% respectively). Independent predictors of recurrence were a CEA ≥5 ng/ml (HR 1.8; 95% CI 1.09-3.00; p = 0.002) and stage II (HR 5.33; 95% CI 1.59-17.90; p = 0.007) and stage III (HR 10.91; 95% CI 3.34-35.60; p=<0.001). A CEA ≥5 ng/ml was associated with a higher risk of death (HR 1.79; 95% CI 1.00-3.19; p = 0.046).

Conclusion: Preoperative CEA levels were associated with age, BMI, ASA and tumour stage. Overall, CEA remains a reliable predictor of recurrence and survival after curative surgery in patients with colorectal cancer.