Combined fecal transferrin test and immuno fecal occult blood test for detecting colorectal cancer and advanced adenoma in asymptomatic and symptomatic populations

Abstract

Recent proteomic studies identified Transferin (TF) as a potential colon cancer biomarker. A dipstick TF test similar to Immuno Fecal Occult Blood Test (IFOBT) was developed, and an initial study showed the TF test had compatible performance characteristics for detecting colon cancer and adenoma. The goal of this study was to evaluate the efficacy of the combination of TF and IFOBT for detecting advanced adenomas and cancer in asymptomatic and symptomatic populations. A total of 1,943 healthy subjects (asymptomatic group) and 201 subjects with various gastrointestinal symptoms (symptomatic group) were recruited for the study. For asymptomatic subjects, one fecal sample was collected for concurrent TF and IFOBT testing. Colonoscopy was performed for individuals positive for either TF or IFOBT. For the symptomatic subjects, each individual underwent TF, IFOBT, and colonoscopy simultaneously. For asymptomatic group, 1,737 individuals tested for TF and IFOBT, 251 subjects (14.5%) showed either TF or IFOBT positivity. Colonoscopy was performed for 193 of the 251 individuals. A total of 3 colorectal cancers and 43 advanced adenomas were detected. Combination of the two tests (either/or) significantly increased the detection rate for colorectal cancers and advanced adenomas compared to IFOBT alone (2.6% vs. 1.6%, P=0.034). In the symptomatic group, the combined test also significantly increased the sensitivity for detecting advanced adenomas and cancer than that of IFOBT alone (77.9% vs. 55.9%, P=0.006), but with decreased specificity (42.1% vs 63.9%, P=0.005). Combined TF and IFOBT test increased the detection rate of colorectal adenoma and cancer in both asymptomatic and symptomatic populations. © 2012 Jin P, et al.