- Immunochemical fecal occult blood tests (iFOBTs) have higher sensitivity for detecting advanced adenomas and neoplasia in the distal colon and rectum than in the proximal colon.
Why this matters
- iFOBTs are among the most widely used noninvasive tests for colorectal cancer (CRC) screening; clinicians interpreting screening results should consider potential differences in diagnostic accuracy, based on anatomical location.
- Researchers analyzed 31 studies assessing iFOBT-based detection of colorectal neoplasms in the proximal colon, distal colon, and rectum (N range, 112-21,805; mean age range, 48-69 years), using a random effects model to calculate pooled sensitivities and specificities.
- Funding: National Natural Science Foundation of China; Chinese Academy of Medical Sciences.
- Researchers found no site-specific differences for iFOBT sensitivities related to CRC (proximal colon: 0.67 [95% CI, 0.62-0.72] vs distal colon/rectum: 0.72 [95% CI, 0.68-0.75]).
- iFOBT had higher sensitivities for detecting distally located advanced adenomas (0.32; 95% CI, 0.30-0.34) and neoplasms (0.38; 95% CI, 0.36-0.40) than for proximally located advanced adenomas (0.24; 95% CI, 0.22-0.25) and neoplasms (0.25; 95% CI, 0.23-0.28).
- Studies had different designs, participant characteristics, and FOBT cutoff values.