Dr. Friedland on a Multimodal Screening Blood Test to Detect CRC

Shai Friedland, MD, a professor of Medicine (Gastroenterology and Hepatology), gastroenterologist, therapeutic endoscopy specialist, large colon polyp specialist, endoscopic ultrasound specialist, biliary specialist, pancreas specialist, gastrointestinal cancer prevention specialist, Stanford Medicine Health Care, discusses a multimodal screening blood test for detecting advanced adenomas and colorectal cancer (CRC).

Data from a study (NCT05127096) evaluating the FirstSight screening blood test were presented at the 2023 Gastrointestinal Cancers Symposium. Findings among 76 patinets with CRC, the test displayed an overall sensitivity of 92.1% (95% CI, 83.6%-97.1%). Additionally, in 112 patients with advanced adenomas, the FirstSight test produced a sensitivity of 54.5% (95% CI, 44.8%-63.9%).

In 259 patients with non-advanced adenomas, the sensitivity was 87.6%. In 144 patients with non-neoplastic findings and 414 patients with a negative colonoscopy, the sensitivity was 89.6% and 92.6%, respectively. Among 850 all-negative patients, the sensitivity was 90.6% (95% CI, 88.4%-92.5%).

Although the 54.5% sensitivity for advanced adenomas does not seem like a high number, when compared with other non-invasive tests, FirstSight demonstrated a higher sensitivity, Friedland says. Moreover, it is important to note advanced adenomas cover a wide range of precancerous lesions; some can be only a little advanced, and others that are much closer to cancer have features such as high-grade dysplasia or are very large, Friedland explains. Notably, all patients who had advanced adenomas with high-grade dysplasia were detected by the test, he adds.

Investigators want to ensure that detect all patients with CRC can have their cancer detected and treated, as well as detect higher-risk advanced adenomas, Friedland says. Since advanced adenomas tend to grow slowly, repeating the blood test after a couple of years following a negative result could properly detect an adenoma, which may be more dangerous at that point. The minimally invasive test could help identify candidates for a colonoscopy, Friedland concludes.