Screening Women Aged 50–59 for CRC Using Fecal Occult Blood Test Produces Outcomes Similar to Men Undergoing Screening Colonoscopy
Average-risk women aged 50–59 years have a lower incidence and mortality of colorectal cancer relative to age-matched men, calling into question the benefit of screening colonoscopy in this age group.
We aimed to determine whether FOBT is an effective initial screening test in 50–59-year-old women.
We conducted a cross-sectional study using a computerized endoscopic report generator. We identified 320,906 individuals who had average-risk screening colonoscopy and 32,369 who had colonoscopy for positive FOBT. The primary outcome was the positive predictive value (PPV) of FOBT for large polyp(s) greater than 9 mm, as a surrogate for advanced neoplasia.
Among patients aged 50–59 years undergoing screening colonoscopy, men were more likely than women to have large polyps (6.3 vs 4.2%, p < 0.0001). Black women undergoing screening colonoscopy had higher rates of large polyps compared to non-Black women. The PPV in FOBT-positive men aged 50–54 (11.5%) and 55–59 (14.4%) was higher than in women aged 50–54 (6.1%) and 55–59 (5.4%). Despite this lower PPV, women aged 50–54 with a positive FOBT had a similar rate of large polyps as 50–54-year-old men undergoing screening colonoscopy (6.1 vs 6.3%, p = 0.626).
CRC screening with FOBT identifies 50–59-year-old men and women with a higher risk of large polyps. Since younger women have a lower risk of large polyps than men, screening with FOBT in 50–59-year-old non-Black women could be an effective screening strategy, with outcomes similar to the use of screening colonoscopy in 50–59-year-old men.
KeywordsColon cancer Screening Polyps FOBT Women
This project was supported with funding from NIDDK U01DK57132 and R33-DK61778-01. In addition, the practice network (Clinical Outcomes Research Initiative) has received support from the following entities to support the infrastructure of the practice-based network: AstraZeneca, Novartis, Bard International, Pentax USA, ProVation, Endosoft, GIVEN Imaging, and Ethicon. The commercial entities had no involvement in this research.
Compliance with ethical standards
Conflict of interest
Dr. Lieberman is the executive director of CORI, a non-profit organization that receives funding from federal and industry sources. This potential conflict of interest has been reviewed and managed by the OHSU and Portland VA Conflict of Interest in Research Committees. All other authors have no potential conflicts of interests to disclose.
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