Department of Pathology, University of São Paulo Medical School, São Paulo, Brazil.
Department of Hematology and Hemotherapy, University of São Paulo Medical School, São Paulo, Brazil.
Ann Diagn Pathol. 2020 Apr;45:151459. doi: 10.1016/j.anndiagpath.2019.151459. Epub 2019 Dec 30.
Aplastic anemia (AA) is a rare disorder characterized by suppression of bone marrow function, which can progress to myelodysplastic syndrome (MDS) or to acute myeloid leukemia (AML). To determine if there are characteristics in bone marrow biopsies in children and adults previously diagnosed with acquired AA, which could predict progression to MDS, we evaluated 118 hypocellular bone marrow biopsies from adults (76 patients) and children (42) diagnosed initially with acquired AA previously to any treatment. Histology was reviewed according to a detailed protocol including Bennett and Orazi criteria for hypocellular myelodysplastic syndrome (h-MDS) and Bauman et al. criteria for refractory cytopenia of childhood (RCC). Twelve patients (10.2%; 6 children and 6 adults) progressed to MDS after a median time of 56 months. Criteria described by Bennett and Orazi suggestive of h-MDS in bone marrow biopsies were detected in 16 cases (13.5%; 8 adults and 8 children), and none in patients that progressed to MDS/AML. Twenty adults' biopsies (26.3%) had the histological criteria used for the diagnosis of pediatric RCC, and none showed MDS/AML evolution. Ten children (23.8%) were reclassified morphologically as RCC, and only one progressed to MDS. In this population with acquired aplastic anemia (AAA), no histological/immunohistochemical (H/IHC) bone marrow findings could discriminate patients with higher risk for myeloid clonal progression, which questions the diagnosis of h-MDS/RCC based only on the finding of dysplasia in the cases without increased blasts and/or the characteristic genetic abnormalities.
再生障碍性贫血（AA）是一种罕见的疾病，其特征是骨髓功能抑制，可进展为骨髓增生异常综合征（MDS）或急性髓系白血病（AML）。为了确定以前诊断为获得性 AA 的儿童和成人的骨髓活检中是否存在可预测向 MDS 进展的特征，我们评估了 118 例来自成人（76 例患者）和儿童（42 例）的低细胞性骨髓活检，这些患者在接受任何治疗之前均被诊断为获得性 AA。根据详细方案进行组织学评估，包括用于低细胞性骨髓增生异常综合征（h-MDS）的 Bennett 和 Orazi 标准以及用于儿童难治性血细胞减少症（RCC）的 Bauman 等人的标准。12 例患者（10.2%；6 例儿童和 6 例成人）在中位数为 56 个月后进展为 MDS。在骨髓活检中检测到的 Bennett 和 Orazi 描述的提示 h-MDS 的标准在 16 例（13.5%；8 例成人和 8 例儿童）中被发现，而在进展为 MDS/AML 的患者中未发现。20 例成人活检（26.3%）具有用于诊断儿科 RCC 的组织学标准，并且无一例显示 MDS/AML 演变。10 例儿童（23.8%）形态学上重新分类为 RCC，仅 1 例进展为 MDS。在该获得性再生障碍性贫血（AAA）人群中，没有组织学/免疫组织化学（H/IHC）骨髓发现可以区分具有髓系克隆进展风险较高的患者，这质疑了仅基于无增加的原始细胞和/或特征性遗传异常的情况下的发育不良来诊断 h-MDS/RCC。
