Quest Diagnostics has announced new pathology and blood test offerings to help identify and assess an individual's risk of Lynch syndrome, also known as hereditary nonpolyposis colorectal cancer (HNPCC), an inherited genetic disorder that significantly increases the risk of colorectal and other cancers. With the new offering, Quest Diagnostics provides a complete menu of guideline-based test services for Lynch syndrome that includes blood and tumor tissue testing. The offering enables physicians to follow professional medical guidelines for patients newly diagnosed with colorectal cancer or for unaffected patients with a strong family history of colorectal or other Lynch-associated cancers. These guidelines, the Evaluation of Genomic Applications in Practice and Prevention (EGAPP), recommend offering screening and genetic testing for Lynch syndrome to individuals newly diagnosed with colorectal cancer regardless of age or family history. A positive result may indicate subsequent blood testing for the patient and family members to assess hereditary risk.
The Lynch syndrome blood-test offering includes a comprehensive blood test panel that evaluates the genes MLH1, MSH2 (and EPCAM terminal deletions), MSH6, and PMS2 for inherited mutations that are responsible for the majority of Lynch syndrome cases. For individuals whose family history or tumor tissue results indicate targeting one or more of these genes, gene-specific tests are available. The offering also includes a menu of validated biopsy-tumor screening options for patients with a diagnosis of colorectal, endometrial, or other Lynch-associated cancers.
Mutations in the genes associated with Lynch syndrome lead to a 40% to 80% chance of developing colorectal cancer (versus a 5% risk in the general population). Approximately one in 35 individuals newly diagnosed with colorectal cancer will have Lynch syndrome. Learn more about Lynch syndrome blood testing.