This is the biggest known operation ever.The Whipple procedure(pancreatoduodenectomy) is the most common operation performed for pancreatic cancer and may be used to treat other cancers such as small bowel cancer. Surgeons remove the head of the pancreas, most of the duodenum (a part of the small intestine), a portion of the bile duct and sometimes a portion of the stomach. After the pancreatoduodenectomy, the surgeon reconstructs the digestive tract. At Mayo Clinic, surgeons perform more than 100 Whipple procedures annually. Patients leave the hospital in an average of 14 days.