Bikhchandani Mihir, Johnson Ryan, Tuan Bertrand, Tefferi Ayalew
California Pacific Medical Center, San Francisco, California, USA.
Mayo Clinic, Rochester, Minnesota, USA.
Acta Haematol. 2018;140(2):67-70. doi: 10.1159/000492485. Epub 2018 Sep 5.
Myeloproliferative disorders with eosinophilia may possess the FIP1L1-PDGFRα gene rearrangement. When this rearrangement is present, imatinib usually results in complete remission. In rare cases of imatinib resistance, there is poor evidence guiding second-line therapy. We present the case of a 71-year-old male who presented with abdominal discomfort, fevers, and leukocytosis with eosinophilia. The patient was diagnosed with a myeloproliferative neoplasm with eosinophilia and FIP1L1-PDGFRα rearrangement after a bone marrow evaluation revealed hypercellular marrow with eosinophilia and fluorescence in situ hybridization identified the FIP1L1-PDGFRα rearrangement. The patient was successfully treated with imatinib. Within months he relapsed and converted into acute myeloid leukemia. The patient was then treated with ponatinib which induced and maintained clinical and hematological remission for 2 months. That ponatinib briefly induced remission in our patient with acute myeloid leukemia arising from a myeloproliferative neoplasm with eosinophilia and FIP1L1-PDGFRα fusion may merit exploration of ponatinib as a potential second-line treatment option for this patient population. This is especially true given the lack of reliable therapies in instances of imatinib resistance.
伴有嗜酸性粒细胞增多的骨髓增殖性疾病可能存在FIP1L1-PDGFRα基因重排。当存在这种重排时，伊马替尼通常会导致完全缓解。在罕见的伊马替尼耐药病例中，指导二线治疗的证据不足。我们报告一例71岁男性患者，其表现为腹部不适、发热以及伴有嗜酸性粒细胞增多的白细胞增多症。骨髓评估显示骨髓细胞增多伴嗜酸性粒细胞增多，荧光原位杂交鉴定出FIP1L1-PDGFRα重排后，该患者被诊断为伴有嗜酸性粒细胞增多的骨髓增殖性肿瘤且存在FIP1L1-PDGFRα重排。该患者接受伊马替尼治疗成功。数月内他复发并转变为急性髓系白血病。随后该患者接受波纳替尼治疗，该药诱导并维持临床和血液学缓解达2个月。波纳替尼能使我们这位由伴有嗜酸性粒细胞增多和FIP1L1-PDGFRα融合的骨髓增殖性肿瘤引发急性髓系白血病的患者短期内获得缓解，这可能值得探索将波纳替尼作为该患者群体潜在的二线治疗选择。鉴于在伊马替尼耐药情况下缺乏可靠的治疗方法，情况尤其如此。
