Genetic testing by cancer site: pancreas.

It is estimated that 5% to 10% of pancreatic cancer is familial. Although there is evidence of a major pancreatic cancer susceptibility gene, the majority of families with multiple cases of pancreatic cancer do not have an identifiable causative gene or syndrome. However, a subset of pancreatic cancer is attributable to known inherited cancer predisposition syndromes, including several hereditary breast cancer genes (BRCA1, BRCA2, and PALB2), CDKN2A, hereditary pancreatitis, hereditary nonpolyposis colorectal cancer, and Peutz-Jeghers syndrome. In addition to explaining a proportion of familial pancreatic cancer, individuals with these conditions are at increased risk for pancreatic cancer. Relatives from familial pancreatic cancer kindreds without one of these identifiable syndromes may have as high as a 32-fold risk of pancreatic cancer, depending on the number of affected first-degree relatives. Such high-risk individuals may benefit from increased surveillance, and strategies for early detection of pancreatic cancer are under evaluation.