Bone marrow pathology in essential thrombocythemia: interobserver reliability and utility for identifying disease subtypes

摘要: The role of histopathology in the diagnosis essential thrombocythemia (ET) is controversial, and there has been little attempt to quantitate interobserver variability. Diagnostic bone marrow trephine biopsy specimens from 370 patients with ET by Polycythemia Vera Study Group (PVSG) criteria were assessed 3 experienced hematopathologists for 16 different morphologic features overall according World Health Organization (WHO) classification. Our results show substantial variability, particularly individual cellular characteristics such as megakaryocyte morphology. Reticulin grade was dominant independent predictor WHO diagnostic category all hematopathologists. Factor analysis identified factors likely reflect underlying biologic processes. One factor related lineage-specific cellularity significantly associated JAK2 V617F status (P < .001), a second clustering, third fibrotic process. No differences could be discerned between labeled having "prefibrotic myelofibrosis" or "true ET" clinical laboratory at presentation, status, survival, thrombosis, major hemorrhage, myelofibrotic transformation. These that histologic described classification are difficult apply reproducibly question validity distinguishing true prefibrotic myelofibrosis on basis subjective criteria. This study registered http://isrctn.org #72251782 http://eudract.emea.europa.eu/ #2004-000245-38.