Screening Older Adults for Colorectal Cancer Adds More Life Years

Extending colorectal cancer (CRC) screening to older population adults between the ages of 76-85 using stool testing results in more life years gained (LYG) compared to blood testing, while both screening options are better than no testing. The findings are being presented at the 2023 American Society of Clinical Oncology (ASCO) Annual Meeting.

CRC screening is both effective and highly recommended. Currently, the U.S. Preventative Services Task Force issues a grade A recommendation for CRC screening between the ages of 50-75, and a grade B recommendation for adults between the ages of 45-49, however the screening recommendation for older adults (ages 76-85) is only grade C. As blood-based CRC screening methods continue to emerge, investigators assessed the benefits of screening the older population using continued multi-target stool DNA (mt-sDNA) or FIT strategies and compared them to the benefit of blood-based tests in individuals over the age of 75.

In this analysis, Dr. Paul J. Limburg (Chief Medical Officer for Screening, Exact Sciences), and colleagues utilized the validated CRC-AIM microsimulation model of triennial mt-sDNA and annual FIT screening (ages 45-75), followed by four possible strategies for the older population (no screening, continued mt-sDNA/FIT, or a modality shift to blood-based screening using either CMS criteria [CMS], or recently reported blood test data from the ECLIPSE study.

Screening Older Adults is a Viable Option

According to the findings, CRC screening the population aged 45-85 yielded 281 life years gained (LYG) with continued mt-sDNA versus 193 with continued FIT. Moreover, mt-sDNA reduced CRC mortality by 70% as compared to 49% by FIT. Furthermore, shifting screening to CMS (76-85 year olds), mt-sDNA/CMS resulted in 279 LYG versus 196 for FIT/CMS.  The investigators’ findings further noted that CRC incidence decreased by 59% (mt-sDNA/CMS) compared to 38% (FIT/CMS), and mortality declined by 69% (mt-sDNA/CMS) as compared to 51% (FIT/CMS).

The results concluded that: “Extending CRC screening to the older population with continued mt-sDNA demonstrated the best health outcomes compared to other modalities. A modality shift after age 75 to blood-based testing resulted in greater LYG as compared to no screening, with performance at CMS criteria yielding better results than BT. Therefore, despite inferior performance, blood-based tests may offer a CRC screening option for older patients who are unable to complete stool testing.”

Source: Ebner D, Kisiel J, Estes C, Vahdat V, Limburg P. The impact of extending CRC screening to the older population. Results from the CRC-AIM microsimulation model. Abstract #10567. Published for the 2023 ASCO Annual Meeting; June 2-5, 2023, Chicago, IL.