Screening Women Aged 50–59 for CRC Using Fecal Occult Blood Test Produces Outcomes Similar to Men Undergoing Screening Colonoscopy

Background: 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. Aims: We aimed to determine whether FOBT is an effective initial screening test in 50–59-year-old women. Methods: 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. Results: 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). Conclusions: 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.