IRF4 and anaplastic large cell lymphoma: DUSP22 rearrangement, which involves the DUSP22/IRF4 (Interferon Regulatory Factor 4) locus on 6p25.3, occurs in −30% of all ALK-negative ALCL and is associated with a very favorable prognosis [5-year overall survival 90%].[9] The prognosis of ALK-negative ALCL with DUSP22 rearrangement is similar to that of the ALK-positive ALCL.[10] The FISH result from skin biopsy showed that this patient had DUSP22 rearrangement.