Incidence of Interval Colorectal Cancer After Negative Results From First-Round Fecal Immunochemical Screening Tests, by Cutoff Value and Participant Sex and Age

Abstract

BACKGROUND & AIMS: We evaluated the incidence of interval cancers between the first and second rounds of colorectal cancer (CRC) screening with the FOB-Gold fecal immunochemical test (FIT), and the effects of different cutoff values and patient sex and age. METHODS: We collected data from participants in a population-based CRC screening program in the Netherlands who had a negative result from a first-round of FIT screening. We calculated the cumulative incidence of interval cancer after a negative result from a FIT and the sensitivity of the FIT for detection of CRC at a low (15 mg Hb/g feces) and high (47 mg Hb/g feces) cutoff value. RESULTS: Among the 485,112 participants with a negative result from a FIT, 544 interval cancers were detected; 126 were in the 111,800 participants with negative results from a FIT with the low cutoff value and 418 were in the 373,312 FIT participants with negative results from a FIT with the high cutoff value. The mean age of participants tested with the low cutoff value was 72.0 years and the mean age of participants tested the high cutoff value was 66.7 years. The age-adjusted 2-year cumulative incidence of interval cancer after a negative result from a FIT were 9.5 per 10,000 persons at the low cutoff value vs 13.8 per 10,000 persons at the high cutoff value (P < .005). The age-adjusted sensitivity of the FIT for CRC were 90.5% for the low cutoff value vs 82.9% for the high cutoff (P < .0001). The FIT identified men with CRC with 87.4% sensitivity and women with CRC with 82.6% sensitivity (P < .001). CONCLUSIONS: In an analysis of data from a FIT population-based screening program in the Netherlands, we found that incidence of interval CRC after a negative result from a FIT to be low. Although the sensitivity of detection of CRC decreased with a higher FIT cutoff value, it remained above 80%.

Transition to quantitative faecal immunochemical testing from guaiac faecal occult blood testing in a fully rolled-out population-based national bowel screening programme

“…23 At the f-Hb threshold of 80 µg Hb/g faeces used in the SBoSP, a reduction in the higher interval cancer rate in females seen with gFOBT 24 is likely since, at lower f-Hb thresholds in The Netherlands, the interval cancer proportion was low in both males and females. 25 The relative difference in PPV for CRC between FIT and gFOBT was high in the least deprived quintile of the population, possibly due to dietary issues. 22 As the f-Hb threshold is lowered to the 80 µg Hb/g faeces used in the SBoSP, the PPV for CRC falls since, although more CRC are detected, the number of colonoscopies that do not detect CRC increases disproportionally, so that the detection rate falls.…”

Psychological distress and quality of life following positive fecal occult blood testing in colorectal cancer screening

“…The FIT uses antibodies that form a complex in the presence of human globin 3 . With a cutoff level of 47 μg Hb/g feces, as currently applied in the Netherlands for referral for colonoscopy, the sensitivity of FIT is 82.9% 4 . Yet, of all FIT‐positives who underwent colonoscopy in the Netherlands between 2014 and 2017, many individuals had false‐positive result as 90 292 individuals (50.1%) had no abnormalities or non‐advanced adenomas (NAADs) 5 .…”

Faecal immunochemical testing in bowel cancer screening: Estimating outcomes for different diagnostic policies

“…• Undetectable f-Hb: delay next screen to three years; 16 • Very low f-Hb: next screen in two years; 17 • Low f-Hb: repeat screening test in three months to assess persistence of bleeding; 18 • Medium f-Hb: flexible sigmoidoscopy to examine the lower part of the colon (distal), and remove any abnormalities found, followed by a further FIT to ascertain whether the cause of the bleeding has been removed; 19 • High f-Hb: colonoscopy. Note that we are not explicitly recommending exactly this strategy or these actions.…”

“…Even prior to the COVID-19 crisis, colonoscopy capacity in England could not cope with this, and the capacity is likely to be even lower for the foreseeable future. Therefore, to maintain acceptable sensitivity to CRC and HRA, one might consider using the quantitative f-Hb more fully, 15 with different actions for different f-Hb categories, for example: Undetectable f-Hb: delay next screen to three years; 16 Very low f-Hb: next screen in two years; 17 Low f-Hb: repeat screening test in three months to assess persistence of bleeding; 18 Medium f-Hb: flexible sigmoidoscopy to examine the lower part of the colon (distal), and remove any abnormalities found, followed by a further FIT to ascertain whether the cause of the bleeding has been removed; 19 High f-Hb: colonoscopy. …”