BACKGROUND This study was conducted to investigate preoperative carcinoembryonic antigen (CEA) as a prognostic factor in colorectal cancer. METHODS: Between January 2000 and July 2011, 1298 patients with primary adenocarcinoma colorectal cancer without metastasis, who underwent curative resection were retrospectively identified. The patients were divided into two groups according to serum CEA level at primary diagnosis: a high CEA (HCEA) group (serum CEA ≥6 ng/mL) and a normal CEA (NCEA) group (serum CEA <6 ng/mL). A 1:1 propensity score matching analysis was applied to reduce bias. Finally, 364 patients were enrolled in this study. Matched variables were age, gender, preoperative chemoradiotherapy, tumor site, cell differentiation and pathologic stage. RESULTS: The clinicopathological characteristics of the two groups did not differ significantly difference. The systemic metastasis rate was 16.5% (30/182) and 25.3% (46/182) in the NCEA and HCEA groups, respectively (p=0.039). There were no significant differences in local recurrence or metastatic sites between groups. The 5-year disease-free survival (DFS) rate of the HCEA group was worse than that of the NCEA group; however, there was no significant difference in overall survival between the two groups. CONCLUSION: Elevated preoperative CEA was related to frequent systemic recurrence and low DFS. Therefore, elevated preoperative CEA could be considered a prognostic factor for worse clinical outcomes in patients with colorectal cancer.
BACKGROUND Prevalence of adenoma in males aged 40-49 years in Korea was higher than expected. The aim of this study was to investigate the prevalence and risk factors of colorectal adenoma in males aged 40-49 years. METHODS: Total 1,902 asymptomatic subjects with a mean age of 47.9±6.7 years, who underwent a screening colonoscopy in a health promotion center of Myongji Hospital from 2010 to 2013 were enrolled in this study. We conducted a case-control study to determine the risk factors for adenoma. The subjects were classified into two groups (adenoma vs. controls). To validate the diagnostic value of carcinoembryonic antigen (CEA) for adenoma, area under the receiver operating characteristic curve (AUROC) was calculated. RESULTS: At least one colorectal adenoma was identified in 385 subjects (20.2%). Among these 385 subjects, 372 subjects were found to have a non-advanced adenoma, 13 subjects had an invasive adenoma. One subject had cancer. Male sex, age, smoking, metabolic syndrome, and elevated CEA level were significantly associated with a colorectal adenoma in univariate analysis. However, metabolic syndrome was not significant in multivariate analysis. In the male group, the AUROC of CEA for colorectal adenoma was 0.600 (0.543 to 0.656) in non-smokers under 50 years of age, and 0.615 (0.540 to 0.690) in smokers under 50 years of age. CONCLUSION: Male sex, smoking, and high levels of CEA seem to be associated with colorectal adenoma. High levels of CEA and smoking may be diagnostic markers for any colorectal adenoma in Korean males aged 40-49 years.