Stage 1 - The disease is limited to a
single lymph node region or to a single extralymphatic organ. Stage II - The disease involves two or more lymph node
regions on the same side of the diaphragm, or involves an
extralymphatic organ and one or more lymph node regions on the same
side of the diaphragm. Stage III - The disease involves lymph node regions on both
sides of the diaphragm and may also be accompanied by localized
involvement of an extralymphatic organ or site or by involvement of
the spleen. Stage IV - The disease shows diffuse or disseminated
involvement of one or more extralymphatic organs or tissues with or
without associated lymph node involvement.