Division of Neurosurgery, Department of Clinical Neuroscience, Faculty of Medicine, University of Miyazaki, 5200 Kihara Kiyotake, Miyazaki, 889-1692, Japan.
Department of Radiology, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan.
Brain Tumor Pathol. 2022 Apr;39(2):88-98. doi: 10.1007/s10014-022-00433-6. Epub 2022 Apr 28.
After the new molecular-based classification was reported to be useful for predicting prognosis, the T2-fluid-attenuated inversion recovery (FLAIR) mismatch sign has gained interest as one of the promising methods for detecting lower grade gliomas (LGGs) with isocitrate dehydrogenase (IDH) mutations and chromosome 1p/19q non-codeletion (IDH mut-Noncodel) with high specificity. Although all institutions could use T2-FLAIR mismatch sign without any obstacles, this sign was not completely helpful because of its low sensitivity. In this study, we attempted to uncover the mechanism of T2-FLAIR mismatch sign for clarifying the cause of this sign's low sensitivity. Among 99 patients with LGGs, 22 were T2-FLAIR mismatch sign-positive (22%), and this sign as a marker of IDH mut-Noncodel showed a sensitivity of 55.6% and specificity of 96.8%. Via pathological analyses, we could provide evidence that not only microcystic changes but the enlarged intercellular space was associated with T2-FLAIR mismatch sign (p = 0.017). As per the molecular analyses, overexpression of mTOR-related genes (m-TOR, RICTOR) were detected as the molecular events correlated with T2-FLAIR mismatch sign (p = 0.020, 0.030. respectively). Taken together, we suggested that T2-FLAIR mismatch sign could pick up the IDH mut-Noncodel LGGs with enlarged intercellular space or that with overexpression of mTOR-related genes.
在新的基于分子的分类被报道有助于预测预后后，T2 液体衰减反转恢复（FLAIR）不匹配征象作为一种有前途的方法引起了人们的兴趣，用于检测具有异柠檬酸脱氢酶（IDH）突变和 1p/19q 非缺失（IDH mut-Noncodel）的低级别胶质瘤（LGG），特异性高。虽然所有机构都可以使用 T2-FLAIR 不匹配征象而没有任何障碍，但由于其敏感性低，该征象并不是完全有帮助的。在这项研究中，我们试图揭示 T2-FLAIR 不匹配征象的机制，以阐明该征象敏感性低的原因。在 99 例 LGG 患者中，22 例 T2-FLAIR 不匹配征象阳性（22%），作为 IDH mut-Noncodel 标志物的该征象的敏感性为 55.6%，特异性为 96.8%。通过病理分析，我们可以提供证据表明，不仅是微囊变化，而且细胞间空间扩大与 T2-FLAIR 不匹配征象有关（p=0.017）。根据分子分析，检测到 mTOR 相关基因（m-TOR、RICTOR）的过表达是与 T2-FLAIR 不匹配征象相关的分子事件（p=0.020、0.030）。总之，我们认为 T2-FLAIR 不匹配征象可以选择具有扩大细胞间空间或过表达 mTOR 相关基因的 IDH mut-Noncodel LGGs。
