Gandhe Nalinikumari, Vekaria Mona, Dabak Vrushali
Internal Medicine, Henry Ford Health System, Detroit, USA.
Hematology and Medical Oncology, Henry Ford Health System, Wyandotte, USA.
Cureus. 2021 Aug 5;13(8):e16914. doi: 10.7759/cureus.16914. eCollection 2021 Aug.
The oncoprotein BCR-ABL has distinct fusion proteins generated from the Philadelphia chromosome translocation, depending on the site of the breakpoint on chromosome 22. The p210 is the hallmark of chronic myeloid leukemia. Only 1% - 2% of patients with chronic myeloid leukemia (CML) demonstrate p190 BCR-ABL. Imatinib mesylate, a tyrosine kinase inhibitor (TKI), specifically targets BCR-ABL, which brought a revolutionary era to the treatment of CML. Although the efficacy of imatinib is widely known, resistance to it has become a pressing challenge in the treatment of CML. CML patients harboring atypical e1a2 transcript (referred to as p190 BCR-ABL) show a poor and short-lived response to first-generation TKI therapy. Patients with p190 BCR-ABL CML should be identified as high-risk patients from the beginning to allow the best chance of a deep molecular response. These patients must be closely monitored during TKI therapy and should be treated upfront with a second-generation TKI. We report a case of p190 BCR-ABL CML with a good response to second-generation TKI.
致癌蛋白BCR-ABL由费城染色体易位产生不同的融合蛋白，这取决于22号染色体上断点的位置。p210是慢性髓性白血病的标志。只有1% - 2%的慢性髓性白血病（CML）患者表现出p190 BCR-ABL。甲磺酸伊马替尼是一种酪氨酸激酶抑制剂（TKI），它特异性靶向BCR-ABL，为CML的治疗带来了一个革命性的时代。尽管伊马替尼的疗效广为人知，但对其产生耐药性已成为CML治疗中的一个紧迫挑战。携带非典型e1a2转录本（称为p190 BCR-ABL）的CML患者对第一代TKI治疗的反应较差且持续时间短。患有p190 BCR-ABL CML的患者应从一开始就被认定为高危患者，以便有最大机会实现深度分子反应。这些患者在TKI治疗期间必须密切监测，并且应该一开始就接受第二代TKI治疗。我们报告了一例对第二代TKI有良好反应的p190 BCR-ABL CML病例。
