Bone Marrow Biopsy Revision According to WHO Criteria in 272 Patients of the Registro Italiano Trombocitemia (RIT): Preliminary Report On Clinical and Histopathological Implications.

Abstract Abstract 4974 Background The bone marrow trephine biopsy (BMB) has a crucial role for the diagnosis of essential thrombocythemia (ET), both according to the PVSG and the WHO criteria. The WHO 2001 criteria enhanced the role of BMB also by distinguishing the true-ET (ET) from the prefibrotic and the early fibrotic chronic idiopathic myelofibrosis. The WHO 2008 criteria, in the JAK2 era, confirmed the diagnostic and prognostic relevance of the histopathological features in ET as well as in the other Ph-neg myeloproliferative neoplasms (MPN). Otherwise, only few validated data are presently available, and the reproducibility in the evaluation of some morphological details is still con…