Association of demographic and treatment variables in long-term colon cancer survival. 
The purpose of this study is to examine demographic and treatment variables because they relate to 5-year survival in colon cancer.  The study design is analysis of 174 471 patients with colon and rectosigmoid cancer as reported to the American College of Surgeons National Cancer Data Base.  Factors associated with a reduced risk of mortality included female gender (hazard ratio = 0.89; 95% confidence interval, 0.87-0.90), education status (hazard ratio = 0.87; 95% confidence interval, 0.85-0.89), increased number of lymph nodes resected (compared with <8, 8-12: hazard ratio = 0.90; 95% confidence interval, 0.89-0.92; >12: hazard ratio = 0.79; 95% confidence interval, 0.77-0.80), and addition of chemotherapy (hazard ratio = 0.69; 95% CI, 0.68-0.71).  African American race (hazard ratio = 1.14; 95% confidence interval, 1.11-1.18) and increasing age correlated with an increased hazard risk (61-75 years: hazard ratio = 1.26; 95% confidence interval, 1.23-1.29; >or=76 years: hazard ratio = 2.15; 95% confidence interval, 2.09-2.21, compared with age <60 years).  Survival in colon cancer is significantly impacted by patient's age, race, gender, and education status but not by income or area of residence.