Utsuki S, Oka H, Tanaka S, Kondo K, Tanizaki Y, Fujii K
Department of Neurosurgery, Kitasato University School of Medicine, Kanagawa, Japan.
Acta Neurochir (Wien). 2003 Aug;145(8):663-6; discussion 666. doi: 10.1007/s00701-003-0078-2.
Medulloblastoma may can be difficult to distinguish from atypical teratoid/rhabdoid tumor (AT/RT), since they resemble each other histologically. We re-examined whether AT/RT was included among cases who had been diagnosed as medulloblastoma. All of fifteen medulloblastomas (10 males and 5 females) diagnosed at the Kitasato University Hospital were collected and stained immunohistochemically. Two cases originally diagnosed as medulloblastoma were reclassified as AT/RT based on histological re-examination including immunohistochemical studies. While these two cases of AT/RT were found during infancy, only one medulloblastoma was found in infancy.Histologically, small rhabdoid cells and large, pale, bland cells were common but typical rhabdoid cells were not seen in the two AT/RTs. Gland-like structures were also seen. The tumor cells in AT/RT, but not those in medulloblastoma, were immunoreactive for vimentin, epithelial membrane antigen and smooth muscle actin. In conclusion, if a diagnosis of medulloblastoma is made histologically, it should be confirmed immunohistologically, since it is difficult to distinguish AT/RT from medulloblastoma. When appropriate treatment was specifically targeted at AT/RT it may improve the outcome.
髓母细胞瘤可能难以与非典型畸胎样/横纹肌样瘤（AT/RT）区分开来，因为它们在组织学上彼此相似。我们重新检查了被诊断为髓母细胞瘤的病例中是否包含AT/RT。收集了北里大学医院诊断的所有15例髓母细胞瘤（10例男性和5例女性），并进行免疫组织化学染色。根据包括免疫组织化学研究在内的组织学重新检查，最初诊断为髓母细胞瘤的2例被重新分类为AT/RT。虽然这2例AT/RT在婴儿期被发现，但仅1例髓母细胞瘤在婴儿期被发现。组织学上，小横纹肌样细胞和大的、苍白的、形态单一的细胞很常见，但在这2例AT/RT中未见到典型的横纹肌样细胞。还可见腺样结构。AT/RT中的肿瘤细胞对波形蛋白、上皮膜抗原和平滑肌肌动蛋白呈免疫反应，而髓母细胞瘤中的肿瘤细胞则无此反应。总之，如果通过组织学诊断为髓母细胞瘤，应通过免疫组织化学进行确认，因为很难将AT/RT与髓母细胞瘤区分开来。当针对AT/RT进行适当治疗时，可能会改善预后。
