CT Colonography Outperforms Stool DNA Testing in Cost-Effectiveness and Clinical Efficacy

A new study published in Radiology has found that CT colonography is a cost-saving and clinically effective method for colorectal cancer screening compared to stool DNA testing. Colorectal cancer is the second leading cause of cancer-related death globally, and routine screening of the colon and rectum can aid in the detection and removal of precancerous polyps, mitigating the need for advanced-stage cancer treatments and the added costs associated with them. The U.S. Preventive Services Task Force and multiple medical societies have lowered the recommended age for colorectal cancer screening to 45 years of age due to the disturbing trend of colorectal cancer diagnoses in younger patients.

Key Takeaways:

• CT colonography is a cost-saving and clinically effective method for colorectal cancer screening compared to stool DNA testing.
• CT colonography reduces colorectal cancer incidence by 70-75% compared to 59% reduction achieved by stool DNA testing.
• The cost of stool DNA testing is nearly $9,000 per quality-adjusted life-year gained (QALY), while CT colonography is found to be cost-effective.
• A hybrid approach to cancer screening, combining CT colonography with colonoscopy for large polyps, achieves the best overall balance in cost-effectiveness and clinical efficacy.
• CT colonography can provide extracolonic screening for conditions such as osteoporosis and cardiovascular disease.

Dr. Perry J. Pickhardt, a study author and John R. Cameron professor of radiology and medical physics at the University of Wisconsin School of Medicine and Public Health, notes that optical colonoscopy is the preferred method of colorectal cancer screening due to its cancer prevention abilities in removing benign precancerous polyps during the procedure. However, less invasive and less expensive screening methods, such as stool DNA testing and CT colonography, are becoming increasingly accessible due to recent Medicare coverage expansions.

Statistics:

• Colorectal cancer is the second leading cause of cancer-related death globally.
• 7.5% of the study population developed colorectal cancer in the absence of screening.
• CT colonography reduces colorectal cancer incidence by 70-75%.
• Stool DNA testing reduces colorectal cancer incidence by 59%.
• The cost of stool DNA testing is nearly $9,000 per quality-adjusted life-year gained (QALY).
• A hybrid approach to cancer screening, combining CT colonography with colonoscopy for large polyps, achieves the best overall balance in cost-effectiveness and clinical efficacy.

Sources:

• "CT Colonography Demonstrates Superior Performance to Multitarget Stool DNA Testing in a Simulation of the U.S. Preventive Services Task Force Recommended Screening Interval." Radiology, 2025.