最近，经常分别用室管膜瘤样或胚胎组织学描述具有 PLAGL1 融合或 PLAGL1/PLAGL2 扩增的神经上皮肿瘤。为了进一步评估具有 PLAG 家族遗传改变的新兴实体，描述了在 St. Jude 遇到的 8 个临床病例的组织学、分子、临床和影像学特征（EWSR1-PLAGL1 融合 n = 6；PLAGL1 扩增 n = 1；PLAGL2 扩增n = 1）。在具有 EWSR1-PLAGL1 重排的幕上神经上皮肿瘤子集 (4/6) 的初始切除中观察到的组织学特征是同时存在室管膜和神经节分化。范围包括室管膜瘤/室管膜瘤样区域内突出的神经节细胞簇，到其他室管膜样组织学中低至中等频率的散布神经节细胞，或具有​​神经节细胞成分的局灶性区域。当存在时，幕上神经上皮肿瘤内室管膜样和神经节特征的组合可能会引起对 EWSR1-PLAGL1 融合的考虑，并提示启动适当的分子测试，例如 RNA 测序和甲基化分析。其中一个 EWSR1-PLAGL1 融合病例在含有小横纹肌样/胚胎细胞簇的区域显示亚克隆 INI1 缺失，并在复发时形成显着的神经节细胞成分。因此，EWSR1-PLAGL1 神经上皮肿瘤是一种可能发生 SMARCB1 获得性失活和 AT/RT 特征发展并导致临床进展的肿瘤类型。相比之下，PLAGL2 和 PLAGL1 扩增病例要么显示胚胎组织学，要么包含具有显着程度结蛋白染色的胚胎成分，这也可能有助于提高对 PLAG 实体存在的考虑。继续汇编相关临床数据和组织病理学结果对于了解具有 PLAG 家族遗传改变的新兴实体至关重要。© 2024。作者。

Neuroepithelial tumors with fusion of PLAGL1 or amplification of PLAGL1/PLAGL2 have recently been described often with ependymoma-like or embryonal histology respectively. To further evaluate emerging entities with PLAG-family genetic alterations, the histologic, molecular, clinical, and imaging features are described for 8 clinical cases encountered at St. Jude (EWSR1-PLAGL1 fusion n = 6; PLAGL1 amplification n = 1; PLAGL2 amplification n = 1). A histologic feature observed on initial resection in a subset (4/6) of supratentorial neuroepithelial tumors with EWSR1-PLAGL1 rearrangement was the presence of concurrent ependymal and ganglionic differentiation. This ranged from prominent clusters of ganglion cells within ependymoma/subependymoma-like areas, to interspersed ganglion cells of low to moderate frequency among otherwise ependymal-like histology, or focal areas with a ganglion cell component. When present, the combination of ependymal-like and ganglionic features within a supratentorial neuroepithelial tumor may raise consideration for an EWSR1-PLAGL1 fusion, and prompt initiation of appropriate molecular testing such as RNA sequencing and methylation profiling. One of the EWSR1-PLAGL1 fusion cases showed subclonal INI1 loss in a region containing small clusters of rhabdoid/embryonal cells, and developed a prominent ganglion cell component on recurrence. As such, EWSR1-PLAGL1 neuroepithelial tumors are a tumor type in which acquired inactivation of SMARCB1 and development of AT/RT features may occur and lead to clinical progression. In contrast, the PLAGL2 and PLAGL1 amplified cases showed either embryonal histology or contained an embryonal component with a significant degree of desmin staining, which could also serve to raise consideration for a PLAG entity when present. Continued compilation of associated clinical data and histopathologic findings will be critical for understanding emerging entities with PLAG-family genetic alterations.© 2024. The Author(s).