The Stool DNA Test Is More Accurate Than the Plasma Septin 9 Test in Detecting Colorectal Neoplasia  David A. Ahlquist, William R. Taylor, Douglas W. Mahoney, Hongzhi Zou, Michael Domanico, Stephen N. Thibodeau, Lisa A. Boardman, Barry M. Berger, Graham P. Lidgard  Clinical Gastroenterology and Hepatology  Volume 10, Issue 3, Pages 272-277.e1 (March 2012) DOI: 10.1016/j.cgh.2011.10.008 Copyright © 2012 AGA Institute Terms and Conditions

Figure 1 Detection rates of large colorectal adenomas by next generation stool DNA and plasma septin 9 tests (n = 22). Median adenoma size was 2.0 cm (range, 1.0–5.4), and 55% were proximal to the splenic flexure. Clinical Gastroenterology and Hepatology 2012 10, 272-277.e1DOI: (10.1016/j.cgh.2011.10.008) Copyright © 2012 AGA Institute Terms and Conditions

Figure 2 Detection rates of colorectal cancer by stool DNA and plasma septin 9 testing. Rates are compared for the overall group, n = 30; the subset without distant metastases (stages I–III), n = 22; and the subset with distant metastases (stage IV), n = 8. Clinical Gastroenterology and Hepatology 2012 10, 272-277.e1DOI: (10.1016/j.cgh.2011.10.008) Copyright © 2012 AGA Institute Terms and Conditions

Figure 3 Comparison of colorectal cancer detection rates by stool DNA and plasma septin 9 testing according to tumor site. See footnote in Table 1 for definitions of proximal and distal. Clinical Gastroenterology and Hepatology 2012 10, 272-277.e1DOI: (10.1016/j.cgh.2011.10.008) Copyright © 2012 AGA Institute Terms and Conditions

Figure 4 Molecular marker release from colorectal neoplasms into target media. This conceptual model shows proportional differences (illustrated by arrow sizes) expected in rates of marker release into the bloodstream via the mechanism of vascular invasion and into the stool via the mechanism of exfoliation during progressive phases of tumorigenesis. Marker release into the bloodstream from precursor lesions is negligible but increases progressively with advancing stages of cancer. In contrast, marker release by exfoliation into stool occurs at comparable rates from large precancers and all stages of cancer. Clinical Gastroenterology and Hepatology 2012 10, 272-277.e1DOI: (10.1016/j.cgh.2011.10.008) Copyright © 2012 AGA Institute Terms and Conditions