Multivariate analysis of factors affecting overall survival in minority-based population of young colorectal cancer patients: A single-institution experience.

Abstract

e14186 Background: Overall survival in colorectal cancer is influenced by obesity, age, gender and stage at diagnosis. However, in minority based populations, effect of the above factors on overall survival has not been studied in any detail. Hence, we undertook this retrospective study to evaluate effect of above factors on overall survival in young colorectal cancer patients. Methods: 1,195 subjects with colorectal cancer treated at John H. Stroger Hospital of Cook County between 2000 and 2008 were retrospectively analyzed. 179 subjects with age 50 years and younger were identified. 146 of 179 subjects with available Body Mass Index (BMI) in kg/m2 were included in the study. Effect of BMI, age, sex, race, LDH and CEA levels, stage, site of tumor, smoking and family history on overall survival was evaluated using standard statistical multivariate analysis. Results: In our population, 22 of 146(15%) were underweight (BMI<20), 56 of 146(38.4%) were normal weight (BMI 20-24.9), 46 of 146(31.5%) were overweight (BMI 25-29.9) and 22 of 146(15%) were obese (BMI >30). Male: female ratio was 1.4:1. 75 of 146(51.7%) were African American, 23 of 146(15.9%) were Caucasians. 50 of 146(34.2%) were stage IV colorectal cancer at diagnosis. On univariate analysis, BMI<20(p=0.031, HR 2.1, 95% CI 1.15-3.82), CEA >4ng/ml (p=0.005, HR 1.93, 95% CI 1.21-3.08) and stage IV colorectal cancer (p<0.001, HR 6.1, 95% CI 2.42-15.53) were significantly associated with decreased overall survival. LDH<200 U/L was significantly associated with improved overall survival (p 0.029, HR 0.6, 95% CI 0.391-0.950). On multivariate analysis, stage IV colorectal cancer was a single significant independent predictor of overall survival (p=0.001, 95% CI 2.47-27.78). CEA>4ng/ml was marginally significant for decreased overall survival (p=0.06, 95% CI 0.978-3.015). On the contrary, no statistically significant difference was found on overall survival with age, BMI>20, gender, race, tumor location, smoking and family history. Conclusions: Advanced stage and CEA >4ng/ml are independent prognostic variables for decreased overall survival in minority based population of young colorectal cancer.