Staging is a way of describing where the disease is located, if or where it has spread, and whether it is affecting the functions of other organs in the body. Doctors use diagnostic tests to determine the disease's stage, so staging may not be complete until all the tests are finished. Knowing the stage helps the doctor to decide what kind of treatment is best and can help predict a patient's prognosis (chance of recovery).

There is no standard staging system for mastocytosis. Doctors will review several factors, including the type of mastocytosis, to learn more about the disease and plan treatment.