Frater John L, Yaseen Nabeel R, Peterson LoAnn C, Tallman Martin S, Goolsby Charles L
Department of Pathology, Northwestern Memorial Hospital and Northwestern University Medical School, Chicago, IL 60611, USA.
Arch Pathol Lab Med. 2003 Mar;127(3):356-9. doi: 10.5858/2003-127-0356-BALWCO.
Acute leukemias demonstrating immunophenotypic features of more than 1 cell lineage are referred to as acute leukemias of ambiguous lineage in the new World Health Organization classification system. A subtype of leukemia of ambiguous lineage is biphenotypic acute leukemia in which the malignant cell population expresses markers of 2 different lineages, most commonly myeloid and either B- or T-lymphoid lineages. This entity has been defined by a scoring system proposed by the European Group for the Immunological Characterization of Acute Leukemias (EGIL), with various markers assigned a score of 2, 1, or 0.5 depending on their specificity for myeloid or lymphoid lineage. Those cases having a score greater than 2 for the myeloid and either the B- or T-lymphoid lineages are biphenotypic acute leukemia in this system. One marker, CD79a, has been so clearly associated with acute lymphoblastic leukemia (ALL) by some researchers that its expression in the presence of blast markers is considered indicative of B-ALL. We describe an unusual case of acute leukemia meeting the criteria for biphenotypic acute leukemia in which CD79a expression was observed in the blast population.
在世界卫生组织新的分类系统中，表现出不止一种细胞系免疫表型特征的急性白血病被称为谱系不明确的急性白血病。谱系不明确的白血病的一个亚型是双表型急性白血病，其中恶性细胞群体表达两种不同细胞系的标志物，最常见的是髓系以及B淋巴细胞系或T淋巴细胞系。该实体已由欧洲急性白血病免疫特征研究组（EGIL）提出的评分系统定义，根据各种标志物对髓系或淋巴系的特异性，分别赋予2分、1分或0.5分。在该系统中，那些髓系以及B淋巴细胞系或T淋巴细胞系得分大于2的病例为双表型急性白血病。一些研究人员发现，一种标志物CD79a与急性淋巴细胞白血病（ALL）的关联非常明确，以至于在存在原始细胞标志物的情况下其表达被认为提示B-ALL。我们描述了一例符合双表型急性白血病标准的不寻常急性白血病病例，其中在原始细胞群体中观察到了CD79a表达。
