Zhou J, Zhao J W, Zheng Y C, Xiao J, Li C W
Institute of Hematology and Blood Diseases Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Tianjin 300020, China.
Zhonghua Xue Ye Xue Za Zhi. 2019 Oct 14;40(10):843-847. doi: 10.3760/cma.j.issn.0253-2727.2019.10.009.
To investigate the genetic screening methods for cryptic acute promyelocytic leukemia (APL) to further explore its clinical prognosis. From June 2016 to November 2018, we collected 373 newly diagnosed APL cases. The patients were retrospected by the results of PML-RARα detections both by RT-PCR and i-FISH, those who harbored positive PML-RARα detection by RT-PCR and negative by i-FISH were chosen. Metaphase FISH and Sanger sequencing were further performed to verify these results. A total of 7 cryptic APL cases were discovered. These cases had tiny fragment of RARα inserted into PML in chromosome 15, formed ins (15;17) . The 7 cryptic APL cases had no PML-RARα gene subtype specificity, involving 5 cases in L subtype, 1 case in S subtype and 1 case in V subtype respectively. After the treatment of retinoic acid and arsenic or anthracyclines, 6 cases achieved complete remission, 1 case died of intracranial hemorrhage on the 6th day of therapy. The size and covering position of PML-RARα probe should be taken into account when PML-RARα was performed by FISH on APL patients. Furthermore, combination with Metaphase FISH could improve the recognition of cryptic APL. There were no differences between the cryptic and common APL patients in terms of clinical features and treatment choices. Cryptic APL patients also had a good response to the therapy of retinoic acid and arsenic or anthracyclines.
为研究隐匿性急性早幼粒细胞白血病（APL）的基因筛查方法，进一步探索其临床预后。2016年6月至2018年11月，我们收集了373例新诊断的APL病例。通过逆转录聚合酶链反应（RT-PCR）和间期荧光原位杂交（i-FISH）检测PML-RARα的结果对患者进行回顾性分析，选择RT-PCR检测PML-RARα阳性而i-FISH检测阴性的患者。进一步进行中期荧光原位杂交（Metaphase FISH）和桑格测序以验证这些结果。共发现7例隐匿性APL病例。这些病例在15号染色体上有RARα小片段插入PML，形成ins(15;17)。7例隐匿性APL病例无PML-RARα基因亚型特异性，分别涉及L亚型5例、S亚型1例和V亚型1例。经维甲酸和砷剂或蒽环类药物治疗后，6例获得完全缓解，1例在治疗第6天死于颅内出血。对APL患者进行FISH检测PML-RARα时，应考虑PML-RARα探针的大小和覆盖位置。此外，联合中期荧光原位杂交可提高对隐匿性APL的识别。隐匿性APL患者与普通APL患者在临床特征和治疗选择方面无差异。隐匿性APL患者对维甲酸和砷剂或蒽环类药物治疗也有良好反应。
