Stool tests are less invasive and less expensive than colonoscopy for colorectal cancer screening.
The traditional fecal occult blood test uses a chemical reaction on a paper card to find traces of blood that leak from pre-cancerous growths and cancer into the stool.
While effective, these types of fecal occult blood tests have some limitations such as a high rate of false-positives.
|Sensitivity for detecting advanced adenomas ranged from 25% to 72%|
|Annals of Internal Medicine|
The new qualitative immunochemical fecal occult blood tests use specific antibodies against human blood components to detect traces of blood in the stool, and may yield fewer false-positive and false-negative results.
To determine if efficacy was similar among the various qualitative immunochemical fecal occult blood tests, Dr Sabrina Hundt compared screening results for six different tests against findings at colonoscopy.
A large difference in diagnostic performance was found between tests.
Sensitivity for detecting advanced adenomas ranged from 25% to 72%, and specificity ranged from 70% and 97%.
Dr Hundt's team concludes, “Not all immunochemical fecal occult blood tests equally effective at detecting colorectal cancer.”