Pre-operative hypoalbuminaemia predicts poor overall survival in rectal cancer: a retrospective cohort analysis

Abstract

BACKGROUND: Serum albumin is a marker of nutrition and inflammation. It has recently emerged as a predictor of outcome after surgery for rectal cancer. Our aim was to evaluate if pre-operative serum albumin would predict survival after resection for rectal cancer. METHOD: 226 Patients with rectal cancer of all stages undergoing resection with curative intent were studied. Kaplan-Meier curves analysed survival based on a pre-operative albumin level of <35 g/L vs. >35 g/L. We sought for significant associations of survival with age, sex, stage, tumour site, use of neoadjuvant chemoradiation, microscopic positive resection margins, differentiation, angio, peri-neural, and lymphovascular invasion using individual variable analysis. Multifactorial analysis was performed using type III analysis with Weibull hazard model and Cox-proportional hazard model. Significance was assigned to a P value <0.05. RESULTS: Of 226 patients (median age- 59 years; range 19 - 88, Male - 54%), forty five (20%) had an albumin level < 35 g/L and was associated with a poor overall survival (P = 0.02). Mean survival in months for <35 g/L vs. >35 g/L was 64.7 (SE - 9.3) vs. 95.8 (SE - 7.0) and 5 year overall survival rates were 49% and 69%. Individual variable analysis revealed age, circumferential margin, stage, perineural, lympho-vascular and angio invasion to be also significant. With multifactorial analysis hypoalbuminaemia (HR = 0.58; 95% CI: 0.35 - 0.95, P = 0.03), advanced stage (HR = 2.0; 95% CI: 1.26 - 3.23, P < 0.01) and positive circumferential margin (HR = 2.2; 95% CI: 1.26 - 3.89, P < 0.01) remained significant. CONCLUSION: Preoperative hypoalbuminaemia is an independent risk factor for poor overall survival in rectal cancer. Advanced tumour stage and circumferential margin positivity were the other associations with poor survival.