A 70-year-old male was referred to our hospital for marked thrombocytosis without anemia. The patient simultaneously presented with an MPL W515L mutation, one of the major driver mutations in essential thrombocythemia (ET), and deletion of 5q, a characteristic cytogenetic abnormality in myelodysplastic syndrome (MDS). Bone marrow examination showed a combination of both mature hyperlobulated megakaryocytes, as found in ET, and small hypolobulated megakaryocytes, typically found in MDS with del(5q). The present case is consistent with the recently proposed category of myeloid neoplasms with isolated del(5q) and an MPN driver mutation.

中文翻译：

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分离的del（5q）和MPLW515L突变的骨髓瘤符合ET的WHO诊断标准。

一名70岁男性因无明显贫血的明显血小板增多症而被转诊至我院。患者同时出现MPL W515L突变，这是原发性血小板增多症（ET）的主要驱动突变之一，并缺失5q（骨髓增生异常综合症（MDS）的特征性细胞遗传学异常）。骨髓检查显示，既有在ET中发现的成熟的超小叶巨核细胞，又有通常在带有del（5q）的MDS中发现的小的低叶的巨核细胞。本案与最近提出的具有分离的del（5q）和MPN驱动程序突变的髓系肿瘤类别一致。