Algorithm for a germline FAP (APC gene) genetic test result in a person without cancer

FAP: familial adenomatous polyposis; VUS: variant of uncertain significance.

* Ensure that the genetic testing is performed properly, the patient identification is correct, and the interpretation of pathogenicity is accurate based on the most recent data analysis.

¶ Pathogenic and likely pathogenic variants are treated the same for purposes of surveillance and risk reduction interventions; these interventions are independent of family history.

Δ VUS lack sufficient information from clinical and bench research to be classified as pathogenic or benign. Continue to seek updated interpretation of pathogenicity periodically (eg, annually).

◊ Examples of FAP-associated cancers include colorectal, small bowel, gastric, thyroid, and brain. Refer to UpToDate content on FAP for the age at which interventions are initiated, the frequency at which they are performed, and the evidence to support these interventions.