Research published in the Annals of Internal Medicine examined the performance of fecal immunochemical tests in detecting colorectal cancer and advanced adenomas.
Researchers examined 31 studies with 120,255 patients and 18 separate fecal immunochemical tests.
What they found:
1. A 10 µg/g threshold resulted in a sensitivity of 0.91 and a negative likelihood ratio of 0.10 for CRC.
2. A greater than 20 µg/g threshold resulted in a sensitivity of 0.95 and a positive likelihood ratio of 15.49 for CRC.
3. However, for advanced adenomas, a 10 µg/g threshold resulted in a sensitivity of 0.40 with a negative likelihood ratio of 0.67 and a specificity of 0.95.
4. A greater than 20 µg/g threshold resulted in a in a specificity of 0.95 and a positive likelihood ratio of 5.86 for advanced adenomas.
5. Researchers found FIT tests had "adequate" performance.
Researchers concluded, "Single-application FITs have moderate to high sensitivity and specificity for CRC, depending on the positivity threshold. Sensitivity of one-time testing for advanced adenomas is low, regardless of the threshold."