Ann Arbor staging system. The Ann Arbor staging system was the landmark lymphoma staging classification system for both Hodgkin lymphoma and non-Hodgkin lymphoma . It is named after the town of Ann Arbor in the US state of Michigan where the Committee on Hodgkin's Disease Staging Classification met in 1971 to agree on it.
stage II: involvement of two or more lymph node regions on the same side of the diaphragm or localized involvement of an extralymphatic organ or site. stage III: involvement of lymph node regions or structures on both sides of the diaphragm.