Adjuvant chemotherapy benefits on patients with elevated carcinoembryonic antigen in stage IIA colon cancer: a SEER-based analysis.

Objective: Indications for adjuvant chemotherapy in stage IIA (T3N0M0) colon cancer are still controversial. The purpose of this study was to evaluate the prognostic value of elevated carcinoembryonic antigen (CEA) levels for cancer-specific survival (CSS) and overall survival (OS) in patients with stage IIA colon cancer. We aimed to examine the impact of adjuvant chemotherapy on OS in stage IIA colon cancer patients with elevated CEA levels.

Methods: Patients with stage IIA colon cancer (N = 3477) diagnosed between 2010 and 2015 were identified using the Surveillance, Epidemiology, and End Results (SEER) database. Kaplan-Meier and Cox proportional hazards regression models were used to assess the prognostic effect of CEA on CSS and OS.

Results: Cox regression analysis demonstrated that CEA was an independent risk factor for CSS and OS in patients with stage IIA colon cancer (CSS: HR = 2.001, 95% CI 1.603-2.499, P < 0.001; OS: HR = 1.530, 95% CI 1.335-1.752, P < 0.001). In the subgroup with elevated CEA, patients received adjuvant chemotherapy had a better OS compared with those did not (χ = 10.585, p = 0.001).

Conclusion: CEA was an independent risk factor for CSS and OS in patients with stage IIA colon cancer. Patients with stage IIA colon cancer with an elevated CEA level might benefit from adjuvant chemotherapy.