There is considerable overlap between the diagnosis of pancreatic cancer and the staging of the cancer. The results of various diagnostic tests will indicate how far the cancer has progressed and determine the stage. Subsequent decicions about treatment will be based upon the stage assigned.
Although different stages carry different prognoses, it is important to remember that the Median isn't the Message. (an excellent article regarding prognoses and statistics by Stephen Jay Gould)
The charts below are part of a very common system used by doctors to stage pancreatic tumors. These particular charts are for pancreatic carcinoma. The staging system varies slightly for tumors of the bile duct or ampulla of Vater.
The stage of a pancreatic cancer is determined by 3 factors: T, N, and M. A value is assigned for each of these factors based on the diagnostic test results. Click on these links to see the how each factor is ranked or scaled.