NEW YORK (GenomeWeb) – A group of experts has recommended that newly diagnosed colorectal cancer patients should receive genetic tests to identify which ones may have Lynch syndrome, the American Gastroenterological Association said today.
The US Multi-Society Task Force on Colorectal Cancer, a group of specialists representing several professional organizations, recommends all new colorectal cancer patients should be tested for evidence of mismatch repair (MMR) deficiency.
The group recommends the universal genetic tumor testing for MMR deficiency as a method for diagnosing Lynch syndrome that is more cost-effective and sensitive than other current methods, and because clinical and prediction models to identify the syndrome have "less-than-optimal sensitivity and specificity," the AGA said.
The task force developed the guidelines to help healthcare providers genetically test and manage patients at risk for and affected by Lynch syndrome, which is the most common cause of inherited colorectal cancer, accounting for around 3 percent, or more than 4,000, of the newly diagnosed cases each year, the AGA said.
The recommendations were published in the AGA's journal, Gastroenterology. The task force members include specialists representing the AGA, the American College of Gastroenterology, and the American Society for Gastrointestinal Endoscopy.
The task force also recommends genetic counseling and germline genetic testing for individuals whose tumors show evidence of MMR deficiency, who have a known MMR gene mutation in the family, who meet clinical criteria for Lynch syndrome and should undergo genetic counseling, or whose risk of Lynch syndrome is higher than 5 percent. This testing not only can confirm the diagnosis of Lynch patients, it can help determine the status of at-risk family members who harbor the MMR mutation and guide management of affected and unaffected family members.