费城染色体阳性急性髓性白血病或新发慢性髓性淋巴母细胞期

Whether acute myeloid leukemia expressing Philadelphia chromosome (Ph+AML) is a distinct clinicopathologic entity and not the de novo presentation of myeloid blast phase of chronic myeloid leukemia (CML-BP) remains controversial [1–4]. Efforts to systematically evaluate and definitively address this issue are hampered by the rare occurrence of this condition. The incidence of Ph+AML is reported to be 1–3% of all cases of AML in older studies, while more recent ones have reported even lower incidence of 0.35–0.9% [2,4–8]. Such discrepancies are likely to be explained by the inclusion in the earlier studies of bi-phenotypic and bi-lineal leukemias, known to express BCR–ABL in high frequ