Risk assessment, genetic testing, and management of Lynch syndrome.
Open Access
- 1 January 2010
- journal article
- Published by Harborside Press, LLC in Journal of the National Comprehensive Cancer Network
- Vol. 8 (1), 98-105
- https://doi.org/10.6004/jnccn.2010.0006
Abstract
Of the estimated 150,000 colorectal cancer (CRC) cases diagnosed annually, approximately 30% have a familial basis and 3% to 5% are from high-penetrance inherited cancer syndromes. Lynch syndrome, or hereditary nonpolyposis colorectal cancer, caused by inherited germline mutations in mismatch repair (MMR) genes, is the most commonly inherited CRC syndrome. It is characterized by young-onset CRC and an increased risk for extracolonic tumors, including gynecologic, urinary tract, and other gastrointestinal cancers. Commercial testing is available for mutations in the MMR genes, but testing all patients with CRC would be economically prohibitive. Therefore, a comprehensive evaluation of a multigenerational family cancer history is essential for the identification of at-risk individuals. The presence of tumors diagnosed at a young age, multiple first- and second-degree relatives with cancer, or 2 or more primary cancers may be indicative of an inherited cancer syndrome and these individuals should undergo genetic evaluation. Genetic test results, when conclusive, can guide management for patients and their families. However, indeterminate test results may provide false reassurance to patients who should be managed as being at higher-than-average risk. Online risk assessment tools and commercial genetic testing offer the potential to identify a greater number of at-risk individuals at an earlier age. However, for these measures to improve outcomes, patients must receive screening recommendations and counseling appropriate for their cancer risk.Keywords
This publication has 57 references indexed in Scilit:
- Colorectal Cancer Risk Perception on the Basis of Genetic Test Results in Individuals at Risk for Lynch SyndromeJournal of Clinical Oncology, 2009
- Genetic testing in gastroenterology: Lynch syndromeBest Practice & Research Clinical Gastroenterology, 2009
- American College of Gastroenterology Guidelines for Colorectal Cancer Screening 2008American Journal Of Gastroenterology, 2009
- The risk of extra‐colonic, extra‐endometrial cancer in the Lynch syndromeInternational Journal of Cancer, 2008
- Genome-wide association scan identifies a colorectal cancer susceptibility locus on 11q23 and replicates risk loci at 8q24 and 18q21Nature Genetics, 2008
- A genome-wide association study identifies colorectal cancer susceptibility loci on chromosomes 10p14 and 8q23.3Nature Genetics, 2008
- Identification of mismatch repair gene mutations in young patients with colorectal cancer and in patients with multiple tumours associated with hereditary non-polyposis colorectal cancerGut, 2006
- Conventional and Tissue Microarray Immunohistochemical Expression Analysis of Mismatch Repair in Hereditary Colorectal TumorsThe American Journal of Pathology, 2003
- A National Cancer Institute Workshop on Hereditary Nonpolyposis Colorectal Cancer Syndrome: Meeting Highlights and Bethesda GuidelinesJNCI Journal of the National Cancer Institute, 1997
- Recommendations for follow-up care of individuals with an inherited predisposition to cancer. I. Hereditary nonpolyposis colon cancer. Cancer Genetics Studies Consortium.1997