Explain the process of "staging" hodgkin's disease and the prognosi?

More testing: Once hodgkin's has been confirmed, further testing is done to "stage" or determine the extent of disease (exam, ct/pet scans, etc). There are 4 stages- stage i is disease in a single area; ii is in two separate areas on one side of the diaphragm; iii is on both sides of diaphragm and IV is widespread. Prognosis is worse the higher the stage but even the worse has 85% chance of remission.