40% of pancreatic cancer patients will have diabetes or hyperglycemia, a condition in which blood sugar is abnormal because of impaired pancreatic function. Of course, there are also concurrent studies showing that people with diabetes have a higher risk of developing pancreatic cancer than people with normal blood sugar. The relationship between diabetes and pancreatic cancer is strong. Blood sugar is too high, it may stimulate the pancreas to work desperately, for a long time, can not tolerate, which led to the occurrence of pancreatic cell cancer; in turn, pancreatic cancer will damage the pancreas to regulate blood sugar function, at the same time will pancreatic cancer cells may also let the body produce insulin resistance, there will be a performance similar to type 2 diabetes manifestation of hyperglycemia manifestation. If blood glucose control is unsatisfactory during clinical treatment, the pancreas needs to be examined to rule out the development of cancer. Including ultrasonography, magnetic resonance or enhanced CT examination, can clarify whether there is the occurrence of insulin tumor. Of course, it is also necessary to pay attention to the examination of pancreatic islet function and blood glucose, etc., which can clarify the diagnosis. Generally, after surgery for pancreatic cancer, if the pancreas is partially removed, it is possible for the blood sugar to return to normal. Therefore, if diabetes is found, it is also necessary to pay attention to exclude the possibility of pancreatic cancer.