Department of Pathology, Shiga University of Medical Science, Otsu, Shiga-ken 520-2192, Japan.
Hum Pathol. 2011 Jan;42(1):141-5. doi: 10.1016/j.humpath.2010.06.012. Epub 2010 Oct 20.
Transient abnormal myelopoiesis in neonates with Down syndrome is an unusual leukemia that spontaneously regresses within several months of life and is thought to arise in the fetal liver. It is largely unknown how the leukemic blasts proliferate and differentiate in fetal tissues. We report the histopathological findings of an autopsy case of a stillbirth with transient abnormal myelopoiesis. Blood vessels in almost all organs were filled with immature leukemic cells, most of which expressed megakaryocyte antigen CD42b. In contrast, leukemic cells infiltrating the tissues, including the pericardium, expressed myeloperoxidase. These findings indicate that leukemic progenitors in transient abnormal myelopoiesis can differentiate along both megakaryocytic and myeloid lineages, which may be influenced by microenvironmental factors. Numerous dysplastic mature/immature megakaryocytes and blasts were present in the liver, whereas the bone marrow contained predominantly myeloid cells at various stages of differentiation, suggesting that the fetal liver is the major organ for proliferation of blasts in transient abnormal myelopoiesis.
唐氏综合征新生儿一过性髓系细胞增生异常是一种不常见的白血病，在生命的几个月内会自发消退，被认为起源于胎肝。白血病细胞在胎儿组织中如何增殖和分化，在很大程度上尚不清楚。我们报告了一例伴一过性髓系细胞增生异常的死胎尸检的组织病理学发现。几乎所有器官的血管中都充满了不成熟的白血病细胞，其中大多数表达巨核细胞抗原 CD42b。相比之下，浸润包括心包在内的组织的白血病细胞表达髓过氧化物酶。这些发现表明，一过性髓系细胞增生异常中的白血病祖细胞可以沿着巨核细胞和髓系两个谱系分化，这可能受到微环境因素的影响。肝脏中存在大量发育不良的成熟/不成熟巨核细胞和原始细胞，而骨髓中则含有不同分化阶段的主要是髓系细胞，这表明胎肝是一过性髓系细胞增生异常中原始细胞增殖的主要器官。
