Lynch Syndrome EGAPP Recommendation
Approximately 3% of people who develop colorectal cancer have an inherited condition known as Lynch syndrome. This condition is also referred to as hereditary nonpolyposis colorectal cancer or HNPCC. People with Lynch syndrome have a greatly increased chance of developing colorectal cancer, especially at a young age (under 50). Close biological relatives (parents, children, sisters, brothers) of people with Lynch syndrome have a 50% chance of inheriting this condition. Other close relatives, such as grandparents, aunts, uncles, cousins, nieces and nephews, are also at increased risk to have Lynch syndrome. If an individual is found to carry a genetic change (mutation) associated with Lynch syndrome, his/her relatives can be tested to determine if they also carry the mutation. Relatives found to have a Lynch syndrome gene mutation can lower their chance of developing or dying from colorectal cancer by having earlier and more frequent colonoscopies.
EGAPP™ Recommendation Statement
“The Evaluation of Genomic Applications in Practice and Prevention (EGAPP™) Working Group found sufficient evidence to recommend offering genetic testing for Lynch syndrome to individuals with newly diagnosed colorectal cancer (CRC) to reduce morbidity and mortality in relatives. We found insufficient evidence to recommend a specific genetic testing strategy among the several examined.”
Summary of Findings on Genetic Testing for Lynch Syndrome
The independent Evaluation of Genomic Applications in Practice and Prevention (EGAPP™) Working Group found good scientific evidence to recommend that all individuals with a new diagnosis of colorectal cancer (regardless of age or family history) be offered genetic testing for Lynch syndrome, in order to help prevent cancer in their close relatives.
There are several laboratory testing approaches available to implement genetic testing for Lynch syndrome in clinical practice. However, the EGAPP™ working group determined that there is not enough evidence to recommend the use of one specific approach.
For the General Public
Patient Summary: Genetic Testing for Lynch Syndrome
For Health Professionals
- Colorectal Cancer, Centers for Disease Control and Prevention
- Lynch Syndrome, Genetics Home Reference, Medline Plus
- Hereditary Non-Polyposis Colon Cancer, Gene Reviews
- Genetics of Colorectal Cancer (PDQ®), National Cancer Institute
- Clinic Directory, GeneTests, NCBI
- Find-A-Counselor, National Society of Genetic Counselors
- Cancer Genetic Services Directory, National Cancer Institute