Saigo K, Nakagawa T, Ryo R, Yamaguchi N
Section of Internal Medicine, Kobe Kyodo Hospital, Japan.
Rinsho Ketsueki. 1995 Nov;36(11):1295-9.
Trisomy 13, as a sole karyotypic abnormality in acute leukemia, has been reported in several cases. However, in chronic myelogenous leukemia (CML), only two cases with this abnormality were reported so far. We describe herein a 68-year-old case with Philadelphia chromosome-negative CML and trisomy 13. Leukocytosis was pointed out during the treatment for other diseases. After 7 months, abrupt increase in leukocyte count (108,000/microliters) and splenomegaly developed. Decreased neutrophil alkaline phosphatase activity and morphological features fulfilled the diagnostic terms for CML. However, the karyotypic analysis revealed trisomy 13 instead of Philadelphia chromosome, and the BCR gene rearrangement was not detected. In cases with acute leukemia accompanied by trisomy 13, malignant transformation of an immature hematopoietic precursor cell has been suggested by the expression of antigens characteristic of both the myeloid and lymphoid lineage. In a few cases with myelodysplastic syndrome, a multipotent stem cell disorder, trisomy 13 has also been reported. From these standpoints, there might be a possibility that trisomy 13 as a sole abnormality in hematologic disorders would be related to tumorigenesis in the levels of multipotent stem cells.
13三体作为急性白血病中唯一的核型异常，已有数例报道。然而，在慢性粒细胞白血病（CML）中，迄今为止仅报道了2例有此异常的病例。我们在此描述1例68岁的费城染色体阴性CML伴13三体患者。在因其他疾病接受治疗期间发现白细胞增多。7个月后，白细胞计数突然升高（108,000/微升）并出现脾肿大。中性粒细胞碱性磷酸酶活性降低及形态学特征符合CML的诊断条件。然而，核型分析显示为13三体而非费城染色体，且未检测到BCR基因重排。在伴有13三体的急性白血病病例中，通过同时表达髓系和淋巴系特征性抗原提示未成熟造血前体细胞发生了恶性转化。在少数骨髓增生异常综合征（一种多能干细胞疾病）病例中也报道了13三体。从这些角度来看，13三体作为血液系统疾病中的唯一异常，有可能在多能干细胞水平上与肿瘤发生相关。
