FOXL2 molecular testing in ovarian neoplasms: diagnostic approach and procedural guidelines
FOXL2 molecular testing in ovarian neoplasms: diagnostic approach and procedural guidelines
复制标题
DOI：
10.1038/modpathol.2012.226
复制
发表时间：
2013-06-01
期刊：
影响因子：
7.5
通讯作者：
Gilks, C. Blake
中科院分区：
文献类型：
--
作者：
Kommoss, Stefan;Anglesio, Michael S.;Gilks, C. Blake
在几乎所有的成人型颗粒细胞肿瘤中都发现了FOXL2的单个复发性体细胞点突变（402C -> G），但在其他卵巢肿瘤中没有发现。成人型颗粒细胞瘤的组织病理学特征可以被多种其他肿瘤模仿，这使得成人型颗粒细胞瘤的诊断具有挑战性。提示FOXL2突变的分子检测可能是诊断成人型颗粒细胞瘤的有用工具。本研究的目的是展示FOXL2突变检测如何用于妇科病理咨询服务，并为FOXL2检测建立明确的程序指南。采用抗FOXL2多克隆抗血清对FOXL2进行免疫组化。如果免疫组化呈阳性，则随后使用TaqMan法分析FOXL2突变状态。进行稀释实验以评估TaqMan试验的敏感性和最低肿瘤细胞要求。20个问题的情况下，评估，其中鉴别诊断后，初步调查包括成人型颗粒细胞瘤。鉴别诊断包括：子宫内膜瘤、上皮间质细胞瘤、幼年颗粒细胞瘤、子宫内膜间质肉瘤等。在所有病例中，FOXL2免疫组化均呈阳性，在6个样本中检测到FOXL2突变，从而确认了成人型颗粒细胞瘤的诊断。TaqMan试验能够可靠地检测到输入DNA在2.5-20 ng范围内的FOXL2突变，并且至少有25%的肿瘤细胞核。临床样本中FOXL2突变状态的分析是鉴别成人型颗粒细胞瘤与其他卵巢肿瘤的有用诊断工具。TaqMan检测至少需要2.5 ng DNA，最佳检测性能为5至10 ng DNA输入。对于肿瘤细胞含量低于25%的标本，应采用激光捕获或针刺宏观解剖。
A single, recurrent somatic point mutation (402C -> G) in FOXL2 has been described in almost all adult-type granulosa cell tumors but not other ovarian neoplasms. Histopathological features of adult-type granulosa cell tumors can be mimicked by a variety of other tumors, making diagnosis of adult-type granulosa cell tumor challenging. It has been suggested that molecular testing for FOXL2 mutation might be a useful tool in the diagnosis of adult-type granulosa cell tumors. The aim of this study was to demonstrate how testing for the FOXL2 mutation can be used in a gynecological pathology consultation service and to establish clear procedural guidelines for FOXL2 testing. Immunohistochemistry for FOXL2 was done using an anti-FOXL2 polyclonal antiserum. If immunohistochemistry was positive, FOXL2 mutation status was subsequently analyzed using a TaqMan assay. A dilution experiment was done to assess the sensitivity and minimum tumor cellularity requirements for our TaqMan assay. Twenty problematic cases were assessed, where the differential diagnosis after the initial investigations included adult-type granulosa cell tumors. Differential diagnoses included: thecoma, Sertoli-Leydig cell tumor, juvenile granulosa cell tumor, endometrial stromal sarcoma and others. In all cases, FOXL2 immunohistochemistry was positive and in six samples the FOXL2 mutation was detected, thus confirming a diagnosis of adult-type granulosa cell tumor. The TaqMan assay was able to reliably detect the FOXL2 mutation with input DNA in the range of 2.5-20 ng, and with a minimum of 25% tumor cell nuclei. The analysis of the FOXL2 mutational status in clinical samples is a useful diagnostic tool in situations where the differential diagnosis is between adult-type granulosa cell tumor and other ovarian tumors. The TaqMan assay requires a minimum of 2.5 ng DNA, with optimal assay performance for 5 to 10 ng DNA input. Laser capture or needle-macrodissection should be undertaken to enrich samples with tumor cell content below 25%.