The role of tissue and serum carcinoembryonic antigen in stages I to III of colorectal cancer-A retrospective cohort study.

PURPOSE: Tissue carcinoembryonic antigen (t-CEA) and serum carcinoembryonic antigen (s-CEA) expression profiles are the most useful tumor markers for the diagnosis and evaluation of colorectal cancer (CRC) worldwide; however, their roles in CRC progression remain controversial. This study aimed to compare the prognostic values of both s-CEA and t-CEA in CRC.

METHODS: A total of 517 patients from January 2006 to December 2010 with stages I-III CRC were retrospectively examined, with 5-year postoperative follow-up and death as end-points. T-CEA expression, s-CEA expression, and clinical pathological parameters were inputted into the SPSS 21.0 software. The Kaplan-Meier method was used to analyze the 5-year disease-free survival (DFS) rate of patients in different tumor node metastasis (TNM) stages based on t-CEA and s-CEA expression.

RESULTS: Tumor differentiation and the number of positive lymph node harvests were significantly different among the t-CEA groups (P < 0.001, P = 0.002); however, clinicopathological features showed no significant difference. The groups with high s-CEA and t-CEA expression had a significantly poorer prognosis than those with low s-CEA (P = 0.021) and t-CEA (P < 0.01) expression, respectively. The multivariate analysis demonstrated that t-CEA was an independent prognostic factor in CRC (P < 0.001), but s-CEA was not (P = 0.339). The 5-year disease-free survival rates among the t-CEA groups were significantly different in stages I, II, and III of CRC (P = 0.001, P < 0.001, P < 0.001), whereas in the s-CEA groups, this difference was observed only in stage III (P = 0.014).

CONCLUSION: This study shows that postoperative t-CEA expression is an independent factor associated with poorer CRC prognosis and has a higher prognostic value than that of preoperative s-CEA expression.