Fecal immunochemical testing (FIT) — a new method of fecal occult blood testing — is now available in the Stanford Clinical Laboratory.

FIT, which uses monoclonal antibody technology, shows superior sensitivity and specificity compared to guaiac-based testing, and unlike the earlier standard method, requires no dietary or medication restrictions, said Tracy George, MD, associate director of the SHC Hematology Lab.

Recently, the American Cancer Society updated its guidelines for early detection of colorectal cancer, stating, "In comparison with guaiac-based tests for the detection of occult blood, immunochemical tests are more patient-friendly and are likely to be equal or better in sensitivity and specificity."

The new fecal immunochemical tests, unlike the guaiac-based test, is specific for lower gastrointestinal bleeding, does not react with animal hemoglobin (i.e. red meat), or peroxidase compounds which may be present in fruits and vegetables, or with medications that can produce false positive results in tests for benign and neoplastic gastrointestinal disorders. It is also not affected by vitamin C, which inhibits the guaiac reaction.

Accuracy of the new test was confirmed in several tests run at Stanford and elsewhere, George explained.

To order the test, check "fecal blood immunologic" on the requisition or electronic order.

For further information, including results of clinical studies, contact George at tigeorge@stanford.edu or 725-5604.