NCCN Publishes Guidelines for Small Bowel Adenocarcinoma

The National Comprehensive Cancer Network (NCCN) has published a set of recommendations for the treatment of small bowel adenocarcinoma (SBA), representing the first treatment guidelines in the United States for the rare type of cancer.

Adenocarcinomas are the most common type of small bowel cancer, making up approximately 3% of all digestive system cancers and affecting an estimated 10,590 people in 2019. While rates of several gastrointestinal malignancies have dropped in recent years, in part due to increases in screening, rates for small bowel cancers have increased 1.8% between 2006 and 2015. There is a lack of consensus on screening for SBA because it is located higher in the gastrointestinal tract and is thus not detected during a colonoscopy. The disease has been linked with herediatary causes such as Lynch syndrome.

“Historically, small bowel adenocarcinoma has been managed in the same way as colorectal cancer, because SBA is rare and, therefore, difficult to study,” said Katrina Pederson, MD, MS, medical oncologist, Siteman Cancer Center at Barnes-Jewish Hospital and Washington University School of Medicine, and member of the NCCN Guidelines Panel for Colorectal Cancer, in a statement. “The new NCCN Guidelines for Small Bowel Adenocarcinoma were created to reflect new research and biologic insights over the past several years that show optimal SBA management can differ from colorectal cancer treatments.”

The NCCN guidelines place an emphasis on incorporating taxanes—a class of diterpenes—into SBA treatment while straying away from the use of epidermal growth factor receptor inhibitors that do not demonstrate a clear benefit. They also highlight developments in genetic testing.

NCCN also recently updated its NCCN Guidelines for Genetic/Familial Risk Assessment: Colorectal Cancer, which includes a step-by-step process for assessing hereditary colorectal cancer syndromes and places an emphasis on the important of genetic counseling.

“Many of these changes reflect the widespread adoption of multi-gene panel testing for hereditary cancer syndromes, which allows assessment for even rare causes of polyposis and other cancer syndromes,” said Heather Hampel, MS, LGC, professor of Human Genetics, The Ohio State University Comprehensive Cancer Center, and member of the NCCN Guidelines Panel for Genetic/Familial Risk Assessment: Colorectal Cancer, in a statement.

According to Hampel, the updated guidelines include a section on the principles of cancer risk assessment and counseling and refine the initial approach to assessing colorectal cancer syndromes. They also include rare genetic causes for multiple adenomatous polyps and updated criteria for evaluation of Lynch syndrome.