Get the Facts: http://genefacts.org Lynch syndrome is a cancer predisposition syndrome caused by inherited mutations in genes responsible for correcting DNA replication errors. Individuals with Lynch syndrome have a greatly increased risk for colorectal, endometrial, and stomach cancers, and a moderately increased risk for other cancers. Key Points 1-3% of colon cancers attributable to Lynch syndrome Dominant inheritance with reduced penetrance (not all patients with mutations will manifest disease) Diagnosis based on clinical and family history, tumor pathology and/or genetic testing Screening and prophylactic surgeries effective in reducing some, but not all cancer risks Mutations in any of several genes can cause the syndrome
HNPCC is a heredity form of Colon Cancer that can be passed through generations of family undetected.