双色双融合荧光原位杂交检测bcr/abl融合基因的临床意义

Clinical significance of dual color-dual fusion translocation fluorescence in situ hybridization in the detection of bcr/abl fusion gene

目的 检测bcr/abl融合基因在慢性粒细胞白血病 (CML)、急性淋巴细胞白血病 (ALL)和真性红细胞增多症 (PV)中的表达 ,以了解其临床意义。方法 采用双色标记双融合bcr/abl探针进行荧光原位杂交 (D FISH) ,检测了 6 7例患者骨髓中期和 (或 )间期细胞。结果 38例CML患者中 ,bcr/abl阳性为 34例 ,占 89.5 % ,其中 1例患者发病时 ,细胞遗传学显示典型的t(9;2 2 ) ,应用干扰素治疗 38个月后 ,bcr/abl基因转为阴性 ;1例异基因外周血造血干细胞移植术后 6 0d的患者 ,细胞形态学及细胞遗传学均显示完全缓解 ,但FISH检测仍有 3.0 %的细胞为bcr/abl基因阳性。 2 4例ALL患者中 ,6例bcr/abl阳性 ,占 2 5 .0 %。 2例PV患者bcr/abl阴性。 3例CML待排的患者bcr/abl均阴性 ,其中1例确诊为原发性血小板增多症 ;1例进一步检测ETO/AML1基因后诊断为M2a;1例仍未能明确诊断。 3例bcr/abl阴性的CML中 ,难治性白血病 2例 ;6例bcr/abl阳性的ALL中 ,难治性白血病 5例。结论 用双色双融合bcr/abl探针进行FISH杂交 ,可准确地检测出bcr/abl融合基因 ,是临床诊断、判定预后及微小残留病的有效监测指标。

Objective To study the expression of bcr/abl hybridized gene in chronic myeloid leukemia ( CML), acute lymphatic leukemia (ALL) and polycythemia vera (PV), and its clinica l significance. Methods The bcr/abl hybridized gene of interphase metaphase cells of bone marrow in 67 s uch patients were investigated with a probe of dual color dual fusion translocation fluorescence in situ hybridization (D FIS H). Results In 38 CML patients, 34 (89.5%) were positive, with one having a typical t(9;22) at first, which changed into negative after having been treated with interferon for 38 months. In another patient, 60 days after post allogeneic peripheral blo od stem cell transplantation (PBSCT), the cytomorphology and cytogenetics were i n completely remission. But 3% cells were bcr/abl positive as detected by D FIS H. Six(25%) of 24 ALL patients were positive for Bcr/abl fusion gene, which was negative in 2 PV patients. Three patients suspected of having CML were also nega tive and one of these three was finally diagnosed as suffering from primary thro mbocythemia and one, acute myeloid leukemia(M 2a ) as detected by ETO/AML 1 gene, though the other one was still not confirmed. Two (67%) of the 3 bcr/abl negative CML patients and 5 (87%) of the 6 bcr/abl positive ALL patients had re fractory leukemia. Conclusion bcr/abl hybridized gene is accurately detected by a probe of dual color dual fu sion translocation fluorescence in situ hybridization, which can serve as an e ffective index for clinical diagnosis, estimation of prognosis and monitor of minimal residual disease in some hematopathies.