Department of Pathology, Dell Children's Medical Center, Austin, TX 78723, USA.
Hum Pathol. 2014 Jan;45(1):185-8. doi: 10.1016/j.humpath.2013.07.039. Epub 2013 Sep 10.
Atypical teratoid/rhabdoid tumor (AT/RT) is a highly aggressive embryonal tumor of the central nervous system, which typically affects young children. A characteristic feature of AT/RT is a polyphenotypic immunoprofile and ultrastructural diversity. The morphologic and antigenic heterogeneity of AT/RT give it the potential to mimic other embryonal central nervous system tumors, epithelial neoplasms or mesenchymal tumors. Alternatively, "collision-type" tumors have been published, in which AT/RT coexists with a separate low-grade central nervous system tumor. Here, we report a case of AT/RT with morphologic and immunohistochemical evidence of extensive ganglioglioma-like differentiation with only a small focal primitive component and minimal rhabdoid cytology. Fluorescence in situ hybridization and immunohistochemistry demonstrated INI1/BAF47 gene/protein losses in both histologic components. To the best of our knowledge, this is the first reported case of AT/RT with extensive ganglioglioma-like differentiation. This unique case supports the notion that routine application of INI1 stains/in situ hybridization can capture AT/RT with unexpected patterns of differentiation.
非典型畸胎样/横纹肌样瘤（AT/RT）是一种高度侵袭性的中枢神经系统胚胎性肿瘤，通常影响幼儿。AT/RT 的一个特征是多表型免疫表型和超微结构多样性。AT/RT 的形态和抗原异质性使其有可能模拟其他胚胎性中枢神经系统肿瘤、上皮性肿瘤或间叶性肿瘤。或者，已经发表了“碰撞型”肿瘤，其中 AT/RT 与另一个单独的低级别的中枢神经系统肿瘤共存。在这里，我们报告了一例具有广泛神经节胶质瘤样分化形态和免疫组织化学证据的 AT/RT，只有一小部分原始成分和最小的横纹肌样细胞学。荧光原位杂交和免疫组织化学显示两种组织学成分中均存在 INI1/BAF47 基因/蛋白缺失。据我们所知，这是首例报道的具有广泛神经节胶质瘤样分化的 AT/RT。这个独特的病例支持这样一种观点，即常规应用 INI1 染色/荧光原位杂交可以捕获具有意外分化模式的 AT/RT。
