There are two reasons why pancreatic cancer patients’ stools are white and oily, the color is white because pancreatic cancer (especially pancreatic head cancer) has a big mass that presses or violates the common bile duct, and the oil is because there is a large amount of fat in the stools. 1. The bigger mass of pancreatic cancer (especially pancreatic head cancer) compresses or violates common bile duct, so that bile can not enter into intestine normally, and most of the color of stools comes from bilirubin in bile, therefore, when bile discharge of pancreatic cancer patients is blocked, the color of stools will show white clay-like stools. 2. The digestion and absorption of fat is mainly through pancreatic enzyme secreted by pancreas. Pancreatic dysfunction of pancreatic cancer patients can not effectively secrete pancreatic enzyme or pancreatic enzyme can not be discharged normally, which affects the digestion and absorption of fatty food in the intestinal tract, and makes the feces containing a large amount of fat presenting the trait of oil. Patients diagnosed with pancreatic cancer should go to the hospital in time and actively cooperate with doctors for treatment.