Better Long-Term Survival in Young Patients with Non-Metastatic Colorectal Cancer after Surgery, an Analysis of 69,835 Patients in SEER Database

OBJECTIVE: To compare the long-term survival of colorectal cancer (CRC) in young patients with elderly ones. METHODS: Using Surveillance, Epidemiology, and End Results (SEER) population-based data, we identified 69,835 patients with non-metastatic colorectal cancer diagnosed between January 1, 1988 and December 31, 2003 treated with surgery. Patients were divided into young (40 years and under) and elderly groups (over 40 years of age). 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: Young patients showed significantly higher pathological grading (p<0.001), more cases of mucinous and signet-ring histological type (p<0.001), later AJCC stage (p<0.001), more lymph nodes (≥12 nodes) dissected (p<0.001) and higher metastatic lymph node ratio (p<0.001). The 5-year colorectal cancer specific survival rates were 78.6% in young group and 75.3% in elderly group, which had significant difference in both univariate and multivariate analysis (P<0.001). Further analysis showed this significant difference only existed in stage II and III patients. CONCLUSIONS: Compared with elderly patients, young patients with colorectal cancer treated with surgery appear to have unique characteristics and a higher cancer specific survival rate although they presented with higher proportions of unfavorable biological behavior as well as advanced stage disease.