NCCN has positioned new recommendations for the assessment of high-risk genetic and familial colorectal cancer (CRC) under Guidelines for Detection, Prevention, and Risk Reduction, paralleling the NCCN Guidelines for Genetic/Familial High-Risk Assessment: Breast and Ovarian. Before 2014, detection and management of hereditary CRC was discussed within the NCCN Guidelines for Colorectal Cancer Screening.
The repositioning of these recommendations is a reflection of the growing awareness of hereditary CRC syndromes, according to Heather Hampel, MS, Professor and Associate Director, Clinical Cancer Genetics Program, The Ohio State University Comprehensive Cancer Center, Columbus, who presented the update at the NCCN 19th Annual Conference.
“We felt the information about the genetic and familial colorectal cancer syndromes had grown, and this was not where clinicians were looking for it,” Ms. Hampel said.
An important new recommendation by the panel is that all patients with newly diagnosed CRC be screened for Lynch syndrome (previously called hereditary nonpolyposis CRC), which occurs in 1 of 35 of these patients. Surveys have shown that approximately three-fourths of NCCN Member Institutions are already adhering to this new recommendation, but there is room for improvement in the wider cancer community, she suggested.
Four DNA mismatch repair genes can lead to Lynch syndrome: MLH1, MSH2, MSH6, and PMS2. Patients who carry mutations in these genes are at high risk for CRC and select other cancers, and they pass the trait along in an autosomal dominant inheritance pattern. NCCN’s proactive position will greatly help identify individuals and their relatives at high risk for a primary or secondary Lynch syndrome-related cancer, Ms. Hampel predicted.
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