Ultracytochemical Characteristics of Megakaryocytic Leukemia in Children. - Comparison with Adult Cases -.

本文对49例急性巨核母细胞白血病（AMKL）和慢性髓性白血病（CML）患儿和成人巨核危象患者的电镜和超微结构细胞化学特征进行了比较。来自患有或不患有唐氏综合症的AMKL儿童的胚细胞表现出不成熟的特征，缺乏典型的α颗粒和分界膜系统。然而，来自AMKL唐氏综合征患者的母细胞有更多的theta，电子朗讯和嗜碱性样颗粒，这表明母细胞比巨核细胞更有可能分化为其他细胞系。成人患者AMKL母细胞血小板过氧化物酶阳性比例高于其他亚组，偶尔含有典型的α颗粒和分界膜系统。这表明成人AMKL的胚细胞比儿童和CML的胚细胞更成熟。通过电镜分析，白血病巨核母细胞在伴有和不伴有唐氏综合征的AMKL儿童、患有AMKL的成人以及处于巨核母细胞危象的CML患者之间存在差异。

Electron microscopic and ultrastructural cytochemical features were compared on 49 children and adults with acute megakaryoblastic leukemia (AMKL) or chronic myelogenous leukemia (CML) in megakaryoblastic crisis. Blast cells from AMKL children with and without Down's syndrome exhibited immature features lacking typical alpha granules and a demarcation membrane system. However, blast cells from AMKL patients with Down's syndrome had more theta, electron-lucent, and basophil-like granules, suggesting that the blast cells had more potential to differentiate into other cell lines than megakaryocytes. The AMKL blast cells of adult patients showed a higher percentage of platelet peroxidase-positivity than other subgroups, and they occasionally contained typical alpha granules and demarcation membrane systems. This indicated that the blast cells of adults with AMKL were more mature than those of children and CML in megakaryoblastic crisis. By electron microscopic analysis, leukemic megakaryoblasts differed between AMKL children with and without Down's syndrome, adults with AMKL, and CML patients in megakaryoblastic crisis.