Why isn't it possible to have pancreas transplants?

It is, but: Pancreas transplants are used to treat diabetes, with variable success. What can't be transplanted in the pancreas' ability to make digestive juices, as surgeons are not able to hook up the ducts when doing the surgery.

We do them!: Pancreas transplants are performed to normalize blood sugar for diabetics with very advanced disease - usually with kidney failure. We can replace the digestive pancreatic functions with enzymes taken by mouth. Txp risks are significant including anti- rejection medications. Very limited availability of organs, so only about 1000 performed in the us each year.