Colorectal cancer and advanced pre-cancers can be detected non-invasively by analyses of exfoliated DNA markers and hemoglobin in stool.
Practical and cost-effective application of a stool DNA-based test for general colorectal cancer screening require high levels of accuracy and high-capacity throughput.
Dr Graham Lidgard and colleagues from Wisconsin, USA optimized an automated sDNA assay, and evaluated its clinical performance.
In a blinded, multi-center, case-control study, the team collected stools from 459 asymptomatic patients before screening or surveillance colonoscopies and from 544 referred patients.
The research team noted that cases included colorectal cancer, advanced adenoma, or sessile serrated adenoma 1 cm, and controls included non-advanced polyps or no colonic lesions.
|Sensitivity for advanced pre-cancers 1 cm was 57%|
|Clinical Gastroenterology and Hepatology|
Samples were analyzed using an automated multi-target sDNA assay to measure β-actin, mutant KRAS, aberrantly methylated BMP3 and NDRG4, and fecal hemoglobin.
The team of doctors used logistic algorithm to to categorize patients as positive or negative for advanced colorectal neoplasia.
At 90% specificity, sDNA analysis identified individuals with colorectal cancer with 98% sensitivity.
The doctors reported that sensitivity for stage I cancer was 95%, for stage II cancer was 100%, for stage III cancer was 96%, for stage IV cancer was 100%, and for stages I–III cancers was 97%.
The researchers found that sensitivity for advanced pre-cancers 1 cm was 57%, 2 cm was 73%, and 3 cm was 83%.
The assay detected AA with high-grade dysplasia with 83% sensitivity.
Dr Lidgard's team commented "We developed an automated, multi-target, sDNA assay that detects colorectal cancer and premalignant lesions with levels of accuracy, previously demonstrated with a manual process."
"This automated high-throughput system could be a widely accessible non-invasive approach to general colorectal cancer screening."