Pericentric inversion of chromosome 9 involving the qh region is relatively common as a constitutional genetic aberration without any apparent phenotypic consequences. However, it has not been established as an acquired abnormality in cancer. Among the three patients reported so far in the literature with acquired inv(9), only one had acute myeloid leukemia (AML). Here we describe an unique case where both chromosomes 9 presented with an acquired pericentric inversion with breakpoints at 9p13 and 9q12 respectively, in a AML patient with aberrant CD7 and CD9 positivity. Additionally, one der(9) also showed short arm deletion at 9p21 to the centromeric region and including the p16 gene. The constitutional karyotype was normal. This is probably the first report describing an acquired inv(9) involving both chromosomes 9 in AML. The possible significance of this inversion is discussed.

中文翻译：

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急性髓系白血病中 9 号染色体的获得性中心倒位。

涉及 qh 区域的 9 号染色体的中心倒位作为一种结构性遗传畸变相对常见，没有任何明显的表型后果。然而，它尚未被确定为癌症的获得性异常。在迄今为止文献报道的三名获得性 inv(9) 患者中，只有一名患有急性髓细胞白血病 (AML)。在这里，我们描述了一个独特的案例，在具有异常 CD7 和 CD9 阳性的 AML 患者中，两条染色体 9 均呈现获得性的中心倒位，断点分别位于 9p13 和 9q12。此外，一个 der(9) 还在着丝粒区域的 9p21 处显示出短臂缺失，包括 p16 基因。体质核型正常。这可能是第一份描述涉及 AML 中两条染色体 9 的获得性 inv(9) 的报告。