it all depends what type of pancreatic cancer the person has. There are many types. Typically from what I have read, if it is adenocarcinoma, the prognosis is not that long. I was diagnosed with islet cell neuroendocrine tumors....my prognosis is much longer. I am not a Dr. Just a patient....you can look at Pancan or look at John hopkins site on pancreatic cancers and you will be able to read up on different types and the prognosis of each type.
Anyway, if you or one of your loved ones have pancreatic cancer, best of luck and fight it hard with all you have.