Department of Pathology, University of Virginia, Charlottesville, VA, USA.
Departments of Pathology & Dermatology, University of Virginia, 415 Lane Road, Hospital Expansion Bldg Room 3024, Charlottesville, VA, 22908, USA.
Curr Hematol Malig Rep. 2018 Aug;13(4):275-288. doi: 10.1007/s11899-018-0456-8.
Acute lymphoblastic leukemias (ALL) are malignant disorders of immature B or T cells that occur characteristically in children, usually under the age of 6 (75%). Approximately 6000 new cases of ALL are diagnosed each year in the USA, 80-85% of which represent B-ALL forms. Most presentations of B-ALL are leukemic, whereas T-ALL presents with a mediastinal mass, with or without leukemic involvement. The revised fourth edition of the World Health Organization (WHO) classification (2017) has introduced some changes in both B and T-ALL. Here, we summarize the categories of lymphoblastic leukemia/lymphomas as defined by the WHO and recent developments in the understanding of this group of hematologic malignancy.
Two provisional categories of B-ALL have now been identified including B-ALL, BCR-ABL1-like, and B-ALL with iAMP21. The Philadelphia chromosome-like B-ALL includes forms of the disease that shares the expression profiling of B-ALL with t(9;22) but lack such rearrangement. The second one shows amplification of part of the chromosome 21. Both entities are associated with worse prognosis. Within the T-ALL group, an early precursor T cell form has now been introduced as a provisional category. Such group demonstrates expression of stem cell and myeloid markers in conjunction with the T cell antigens. The current review summarizes the recent updates to the WHO classification.
急性淋巴细胞白血病（ALL）是一种幼稚 B 或 T 细胞的恶性疾病，通常发生在儿童期，年龄通常小于 6 岁（75%）。在美国，每年约有 6000 例 ALL 新发病例，其中 80-85%为 B-ALL 形式。大多数 B-ALL 表现为白血病，而 T-ALL 则表现为纵隔肿块，伴或不伴白血病浸润。世界卫生组织（WHO）修订的第四版分类（2017 年）在 B 和 T-ALL 中都引入了一些变化。在这里，我们总结了 WHO 定义的淋巴母细胞白血病/淋巴瘤的类别，以及对这组血液恶性肿瘤的理解的最新进展。
现在已经确定了两种暂定的 B-ALL 类别，包括 B-ALL、BCR-ABL1 样和伴有 iAMP21 的 B-ALL。费城染色体样 B-ALL 包括与 t(9;22)具有相同表达谱但缺乏这种重排的疾病形式。第二种情况显示部分 21 号染色体的扩增。这两种实体都与预后较差有关。在 T-ALL 组中，现在已经引入了一种早期前体细胞 T 细胞形式作为暂定类别。该组表现出干细胞和髓系标志物的表达，同时伴有 T 细胞抗原。本综述总结了 WHO 分类的最新更新。
