Inflammation-Based Prognostic System Predicts Postoperative Survival of Colorectal Cancer Patients with a Normal Preoperative Serum Level of Carcinoembryonic Antigen

Although carcinoembryonic antigen (CEA) is a valuable indicator for estimating the progression of colorectal cancer (CRC), some patients with advanced CRC show no elevation of the CEA level. On the other hand, inflammation-based prognosis, assessed by the Glasgow Prognostic Score (GPS), has been established as one of the important prognostic factors of survival after surgery for several types of cancer. We estimated the postoperative survival of CRC patients with a normal preoperative serum level of CEA on the basis of the GPS. Among 491 patients who had undergone elective CRC surgery, 271 with a normal preoperative serum CEA level (a parts per thousand currency sign5.0 ng/ml) were enrolled. Uni- and multivariate analyses were performed to evaluate the relationship to overall survival. Kaplan-Meier analysis and log rank test were used to compare the survival curves between patients with GPS 0 (group A), and 1 or 2 (group B). Univariate analyses using clinical characteristics revealed that lymphatic invasion, lymph node metastasis, platelet count, the serum levels of CEA and C-reactive protein, tumor, node, metastasis staging system (stage 0, I, II/III, IV), and the GPS (0/1, 2) were associated with overall survival. Among these characteristics, multivariate analysis demonstrated that the GPS and platelet count were associated with overall survival. Kaplan-Meier analysis and log rank test demonstrated a significant difference in overall survival between groups A and B (P < 0.001). Even if CRC patients have a normal preoperative serum level of CEA before surgery, the GPS is able to predict their postoperative survival.