Detection of Colorectal Cancer by Faecal α1-Antitrypsin

Abstract

Alpha1-antitrypsin was measured in 5-day faecal collections from patients with colorectal cancer or adenomatous polyps and a symptomatic control group. Collections were homogenized and lyophilized prior to measurement of α1-antitrypsin by radial immuno-diffusion. Colorectal cancer dry weight concentrations were significantly higher than the symptomatic control results, with 57% having results greater than 95% normal values of this control group. There was no significant difference between adenomatous polyp dry weight concentrations and symptomatic control results. Wet weight concentrations were calculated from wet/dry ratios. Colorectal cancer wet weight concentrations were significantly higher than symptomatic control results with 48% having results greater than 95% normal values of this control group. Alpha1-antitrypsin was also measured in non-lyophilized samples from an asymptomatic control group ( n = 39). Colorectal cancer wet weight concentrations were significantly higher than asymptomatic control results, with 62% having results greater than 95% normal values of this control group. Faecal α1-antitrypsin measurement deserves further assessment for use in detecting colorectal cancer.