Pathological Features and Survival Outcomes of Young Patients with Operable Colon Cancer: Are They Homogeneous?

Objective: To compare the pathological features and survival outcomes at different age subgroups of young patients with colon cancer. Methods: Using Surveillance, Epidemiology, and End Results (SEER) population-based data, we identified 2,861 young patients with colon cancer diagnosed between 1988 and 2005 treated with surgery. Patients were divided into four groups: group 1 (below 25 years), group 2 (26-30 years), group 3 (31-35 years) and group 4 (36-40 years). Five-year cancer specific survival data were obtained. Kaplan-Meier methods were adopted and multivariable Cox regression models were built for the analysis of long-term survival outcomes and risk factors. Results: There were significant different among four groups in pathological grading, histological type, AJCC stage, current standard (>= 12 lymph nodes retrieval), mean number of lymph nodes examined and positive lymph nodes (p<0.001). The 5-year cause specific survival was 71.0% in group 1, 75.1% in group 2, 80.6% in group 3 and 82.5% in group 4, which had significant difference in both univariate (P = 0.002) and multivariate analysis (P = 0.041). Conclusions: Young patients with colon cancer at age 18-40 years are essentially a heterogeneous group. Patients at age 31-35, 36-40 subgroups have more favorable clinicopathologic characteristics and better cancer specific survival than below 30 years.