Much confusion about the exact classification and clinicopathological features of this subgroup of NHL was clarified with the identification of NPM-ALK (nucleophosmin-anaplastic lymphoma kinase) as the oncogene created by the t(2;5) (Morris et al., 1994).     ///    "With the discovery of NPM-ALK as the specific lymphoma gene mutation, this NHL subtype could be redefined on the molecular level. "