The 2016 World Health Organization entity ‘Myeloid/lymphoid neoplasms with eosinophilia and rearrangement of PDGFRA, PDGFRB or FGFR1, or with PCM1-JAK2’ encompasses a group of rare neoplasms that result from the formation of a fusion gene that leads to expression of an aberrant tyrosine kinase. This entity also contains variant JAK2 fusion partners, and detection of this defining event can be facilitated by various cytogenetic and molecular methods. Cryptic rearrangements of 9p24/JAK2 can be particularly challenging to identify. We describe the use of chromosomal microarray analysis (CMA), fluorescence in situ hybridization (FISH) with a probe for JAK2, and genomic mate pair analysis to describe a complex karyotype with a t(9;22) that produced a functional BCR-JAK2 fusion, leading to the appropriate diagnosis for the patient. This case highlights the importance of using an integrated genomic approach to fully define complex aberrations to assign proper diagnoses.

2016年世界卫生组织实体'嗜酸性粒细胞增多和PDGFRA，PDGFRB或FGFR1或PCM1-JAK2重排的髓样/淋巴瘤'涵盖了一组罕见肿瘤，这些罕见肿瘤是由于融合基因的形成而导致异常表达的结果酪氨酸激酶。该实体还包含变异的JAK2融合伴侣，并且可以通过各种细胞遗传学和分子方法促进对该定义事件的检测。9p24 / JAK2的隐蔽重排可能很难识别。我们描述了使用JAK2探针的染色体微阵列分析（CMA），荧光原位杂交（FISH），以及基因组配对分析，以描述具有at（9; 22）的复杂核型，该核型产生功能性BCR-JAK2融合蛋白，从而为患者提供适当的诊断。这种情况凸显了使用集成基因组方法全面定义复杂像差以分配正确诊断的重要性。