Genetic testing for hereditary gastrointestinal cancer syndromes: Interpreting results in today's practice
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Purpose of review
Advances in genomics have led to the discovery of multiple predisposition genes linked to increased risk for gastrointestinal (GI) cancer. The goal of this review is to assist physicians and allied health care professionals in understanding the current paradigm shift in clinical genetic testing for hereditary GI cancer predisposition syndromes; with a focus on multigene panel testing (MGPT) and test results interpretation. Additionally, this review introduces direct-to-consumer and at-home genetic testing. Both delivery models are increasing in popularity and clinicians will be expected to address results from patients who utilize these approaches.
Technological advancement and reduced costs have transformed the genetic testing approach from single syndrome genetic testing to broad-based MGPT. MGPT has the benefit of aiding in efficient genetic diagnosis; however, clinicians should be knowledgeable of possible results including variants of uncertain significance, secondary findings, and pathogenic variants within high- and low-to-moderate risk genes, as well as genes for which risks are ill-defined.
The landscape of clinical cancer genetics continues to evolve rapidly. Timely updates are critical to ensure the medical community is familiar with current considerations and ongoing challenges regarding genetic testing for hereditary GI cancer susceptibility.
KeywordsMultigene panel testing variant interpretation gastrointestinal cancer susceptibility cancer genetics direct-to-consumer genetics
NIH/NIDDK grants K08DK106489 and R03DK120946 (BWK), The Lustgarten Family Colon Cancer Research Fund (BWK), and The Jason and Julie Borrelli Lynch Syndrome Research Fund (BWK).
Compliance with ethical standards
Conflict of interest
Bryson Katona reports grants from NIH/NIDDK, paid travel related to a clinical trial from Janssen, and is a consultant for Exact Sciences. Jacquelyn Powers reports consulting for CareVive. Jessica Ebrahimzadeh declares that she has no conflict of interest.
Human and animal rights and informed consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
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