Ependymomas are neuroepithelial tumors that differentiate along the ependymal cell lineage, a lining of the ventricles of the brain and the central canal of the spinal cord. They are rare in adults, but account for around 9% of brain tumors in children, where they usually have an aggressive course. Efficient stratification could lead to improved care but remains a challenge even in the genomic era. Recent studies proposed a multivariate classification system based on tumor location, age, and broad genomic findings like global patterns of methylation and copy number variants (CNVs). This system shows improved prognostic utility, but is relatively impractical in the routine clinical setting because it necessitates multiple diagnostic tests. We analyzed 13 intracranial grade II and III ependymoma specimens on a DNA microarray to identify discrete CNVs that could support the existing classification. The loss of chr22 and the gain of 5p15.31 were common throughout our cohort (6 and 11 cases, respectively). Other CNVs correlated well with the previously proposed classification system. For example, gains of chr20 were unique to PF-EPN-B tumors of the posterior fossa and may differentiate them from PF-EPN-A. Given the ease of detecting CNVs using multiple, clinically validated methods, these CNVs should be further studied to confirm their diagnostic and prognostic utility, for incorporation into clinical testing algorithms.

室间隔瘤是沿上皮细胞谱系，脑室和脊髓中央管排列的神经上皮肿瘤。它们在成年人中很少见，但约占儿童脑瘤的9％，在儿童中，它们通常具有侵略性病程。有效的分层可以改善护理水平，但即使在基因组时代，仍然是一个挑战。最近的研究提出了一种基于肿瘤位置，年龄和广泛的基因组发现（如甲基化和拷贝数变异（CNV）的整体模式）的多变量分类系统。该系统显示出改善的预后效用，但在常规临床环境中相对不切实际，因为它需要进行多次诊断测试。我们在DNA微阵列上分析了13个颅内II和III级室间隔膜瘤标本，以识别可以支持现有分类的离散CNV。在整个队列中，chr22的丢失和5p15.31的增加是常见的（分别为6例和11例）。其他CNV与先前提出的分类系统具有很好的相关性。例如，chr20的获得是后颅窝的PF-EPN-B肿瘤特有的，可能使它们与PF-EPN-A区别开来。考虑到使用多种经过临床验证的方法检测CNV的简便性，应将这些CNV进行进一步研究以确认其诊断和预后功能，以便将其纳入临床测试算法中。其他CNV与先前提出的分类系统具有很好的相关性。例如，chr20的获得是后颅窝的PF-EPN-B肿瘤特有的，可能使它们与PF-EPN-A区别开来。考虑到使用多种经过临床验证的方法检测CNV的简便性，应将这些CNV进行进一步研究以确认其诊断和预后功能，以便将其纳入临床测试算法中。其他CNV与先前提出的分类系统具有很好的相关性。例如，chr20的获得是后颅窝的PF-EPN-B肿瘤特有的，可能使它们与PF-EPN-A区别开来。考虑到使用多种经过临床验证的方法检测CNV的简便性，应将这些CNV进行进一步研究以确认其诊断和预后功能，以便将其纳入临床测试算法中。