Predictive value of mucinous histology in colon cancer: a population-based, propensity score matched analysis

BACKGROUND: This investigation aimed to assess whether mucinous histology impacts overall (OS) and cancer-specific survival (CSS) in colon cancer. METHODS: Colon cancer patients who underwent surgery between 2004 and 2011 were identified in the Surveillance, Epidemiology, and End Results database. OS and CSS were assessed using Cox regression and propensity score methods. RESULTS: Out of 121 628 patients, 12 863 (10.6%) had a mucinous histology. Five-year OS and CSS for mucinous adenocarcinoma were 54.4% (95% CI: 53.4–55.5%) and 66.5% (95% CI: 65.5–67.5%) compared with 60.2% (95% CI: 59.8–60.5%) and 71.9% (95% CI: 71.5–72.2%) for non-mucinous adenocarcinoma (P<0.001). This survival disadvantage disappeared in multivariable analyses (hazard ratio (HR)=1.02, 95% CI: 0.99–1.05, P=0.269 and HR=1.03, 95% CI: 0.99–1.06, P=0.169), and after propensity score matching (OS: HR=0.99, 95% CI: 0.93–1.04, P=0.606 and CSS: HR=0.99, 95% CI:0.92–1.06, P=0.783). CONCLUSIONS: In this population-based investigation, a mucinous histology did not negatively impact survival. Hence, the present study does not provide evidence to change treatment strategies in patients with mucinous adenocarcinoma of the colon.