title: Rectal mucosal quantitative galactose oxidase-Schiff reaction as an early detection biomarker for colorectal cancer: comparison to fecal occult stool blood test.
abstract: The galactose oxidase-Schiff (GOS) reaction detects D-galactose-β-[1,3]-N-acetyl-D-galactosamine. This is a T-antigen expressed in mucus from malignant cells and colonic mucosa adjacent to cancer but not in normal mucosa. Previous studies using a qualitative GOS assay proved to be of limited value for the detection of colorectal neoplasia. We used a newly developed quantitative GOS assay to determine its potential as an early detection biomarker for colorectal cancer. We completed a multi-center, prospective, cross-sectional cohort validation study consisting of 70 normal controls, 23 high-risk normal patients (polyp history or family history of colorectal cancer (CRC) with currently normal colonoscopy), 137 patients with adenomatous polyps, and 69 with colorectal cancers. Prior to colonoscopy, two samples of stool were collected via a rectal exam: one for FOBT, and one for GOS. The area under the ROC curve (AUC) for detecting colonic adenomas and cancer for normal colons, computed with logistic regression was 0.69 for GOS, 0.62 for FOBT, and 0.73 for GOS combined with FOBT. Adding GOS to FOBT did not significantly change the ROC of FOBT alone. GOS does not appear to be a suitable marker of colorectal neoplasia.
authors: University of Michigan, Department of Family Medicine, Ann Arbor, MI, USA. mruffin@umich.ed
authors: Mack T
authors: MT
authors: Ruffin
authors: Daniel P
authors: DP
authors: Normolle
authors: Michael J
authors: MJ
authors: Evelegh
authors: John A
authors: JA
authors: Baron
authors: Robert S
authors: RS
authors: Bresalier
authors: Norman E
authors: NE
authors: Marcon
authors: Sapna
authors: S
authors: Syngal
authors: D Kim
authors: DK
authors: Turgeon
authors: Melissa K
authors: MK
authors: Tuck
authors: Dean E
authors: DE
authors: Brenner
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000957:Antigens, Viral, Tumor / Q000032:analysis*; D014408:Biomarkers, Tumor / Q000032:analysis*; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D004187:Disaccharides / Q000032:analysis*; D055088:Early Detection of Cancer; D005260:Female; D005685:Galactans / Q000032:analysis*; D005692:Galactose Oxidase / Q000737:chemistry*; D006801:Humans; D007413:Intestinal Mucosa / Q000737:chemistry*; D008297:Male; D008875:Middle Aged; D009780:Occult Blood; D011446:Prospective Studies; D012007:Rectum / Q000737:chemistry*; D012394:Rosaniline Dyes / Q000737:chemistry
chemical_list: D000957:Antigens, Viral, Tumor; D014408:Biomarkers, Tumor; D004187:Disaccharides; D005685:Galactans; D012394:Rosaniline Dyes; C476677:Schiff's reagent; C443716:galactosyll(1,3)-N-acetylgalactosamine; D005692:Galactose Oxidase