Approximately 5% to 10% of patients with pancreatic cancer have one or more first-degree relatives with this disease. A subset of these individuals have a hereditary form of pancreatic cancer designated by association with such hereditary disorders as familial adenomatous polyposis, hereditary nonpolyposis colorectal cancer, hereditary pancreatitis, or familial atypical multiple mole melanoma (FAMMM) syndrome. A subset of those FAMMM kindred with the CDKN2A (p16) germline mutation that expresses both pancreatic cancer and malignant melanoma may constitute a new hereditary pancreatic cancer-prone syndrome.