Ann Arbor Classification: Stage II: Involvement of two or more lymph node regions on the inferior side of the diaphragm (II) or localized involvement of a single associated extralymphatic organ or site and its regional lymph node(s) with or without involvement of other lymph node regions on the same side of the diaphragm (IIE). Note: The number of lymph node regions involved may be indicated by a subscript. [from NCI]