Article Text
Abstract
Background As screening methods for colorectal cancer (CRC) are limited by uptake and adherence, further options are sought. A blood test might increase both, but none has yet been tested in a screening setting.
Objective We prospectively assessed the accuracy of circulating methylated SEPT9 DNA (mSEPT9) for detecting CRC in a screening population.
Design Asymptomatic individuals ≥50 years old scheduled for screening colonoscopy at 32 US and German clinics voluntarily gave blood plasma samples before colon preparation. Using a commercially available assay, three independent blinded laboratories assayed plasma DNA of all CRC cases and a stratified random sample of other subjects in duplicate real time PCRs. The primary outcomes measures were standardised for overall sensitivity and specificity estimates.
Results 7941 men (45%) and women (55%), mean age 60 years, enrolled. Results from 53 CRC cases and from 1457 subjects without CRC yielded a standardised sensitivity of 48.2% (95% CI 32.4% to 63.6%; crude rate 50.9%); for CRC stages I–IV, values were 35.0%, 63.0%, 46.0% and 77.4%, respectively. Specificity was 91.5% (95% CI 89.7% to 93.1%; crude rate 91.4%). Sensitivity for advanced adenomas was low (11.2%).
Conclusions Our study using the blood based mSEPT9 test showed that CRC signal in blood can be detected in asymptomatic average risk individuals undergoing screening. However, the utility of the test for population screening for CRC will require improved sensitivity for detection of early cancers and advanced adenomas.
Clinical Trial Registration Number: NCT00855348
- Colorectal Cancer Screening
- Methylation
- Colonoscopy
- Colorectal Adenomas
- Colorectal Neoplasm
This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 3.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/3.0/
Statistics from Altmetric.com
Supplementary materials
Supplementary Data
This web only file has been produced by the BMJ Publishing Group from an electronic file supplied by the author(s) and has not been edited for content.
Files in this Data Supplement:
- Data supplement 1 - Online supplement
- Data supplement 2 - Online appendix