IRF4 mutation in lymphoma – pro
The testing appears to be FISH for IRF4 mutation. Interferon regulatory factor IRF4 .The World Health Organization (WHO) is considering adding this entity to its list of lymphomas. These lymphomas most typically occur in Waldeyer ring and/or cervical lymph nodes and are low stage. They may have a follicular, follicularand diffuse, or pure diffuse growth pattern resembling FL grade 3B or aDLBCL. Strong IRF4/MUM1 expression is seen usually with BCL6 and a high proliferative fraction. BCL2 and CD10 are also expressed in more than half of the cases with a minority CD51. They are most often of germinal center type, particularly based on gene expression profiling(GEP) studies.26Most cases have IG/IRF4 rearrangements sometimes together withBCL6rearrangements but they uniformly lackBCL2rearrangements. Some cases that also seem to belong in this category lack a demonstrable IRF4 rearrangement but have strong IRF4/MUM1 expression.23This lymphoma is considered to be more aggressive than other pediatric-type FL but patients, at least when treated, have done very well.
The 2016 revision of the World Health Organization classification oflymphoid neoplasms. BLOOD, 19 MAY 2016xVOLUME 127, NUMBER 202375
Talaverria I, Philipp C, Oschlies I, et al;Molecular Mechanisms in Malignant LymphomasNetwork Project of the Deutsche Krebshilfe;German High-Grade Lymphoma Study Group;Berlin-Frankfurt-M ̀ˆunster-NHL Trial Group.Translocations activating IRF4 identify a subtypeof germinal center-derived B-cell lymphomaaffecting pre