间变性节细胞胶质瘤复发为幕上原始神经外胚层肿瘤一例报告并文献复习

背景与目的：间变型节细胞胶质瘤非常少见,恶变总是发生在胶质成分。目前已有少量病例显示神经元成分的恶性转化。本文报道一例原发瘤为间变性节细胞胶质瘤,术后8个月复发为幕上原始神经外胚层肿瘤的病例。方法：观察并分析原发瘤和复发瘤的病理形态特征和免疫组化标记。结合文献讨论间变性节细胞胶质瘤转变为幕上原始神经外胚层肿瘤的可能机制。结果：患儿8岁。镜下见第一次切除的左颞叶肿瘤：部分区域肿瘤细胞密集分布。细胞较小,核染色较深,部分瘤细胞呈小片状,细胞稍大,核圆形或多角形,染色质淡。肿瘤组织中另可见散在或聚集向神经元分化的不同阶段的肿瘤细胞。细胞较大,有明显淡红染的胞浆,胞核空泡状,有核仁。有的似分化较成熟的节细胞。网状染色见瘤组织中纤维组织明显增生。免疫组化结果显示：GFAP灶性（＋）、NSE（＋）、S100（＋）、Nestin（＋）、VIM（＋）、Des（＋）。似神经元分化的大细胞则有NSE和S-100的阳性表达。病理诊断：伴有纤维增生的间变性节细胞胶质瘤。术后8个月左颞部复发肿瘤中除了仍见明显的纤维组织增生外,另见小或中等大小的肿瘤细胞密集排列,瘤细胞更异型,核分裂多见。未见较成熟分化的细胞。免疫组化显示：GFAP灶性（＋）、S100（＋）、NFP（＋）、Neuronal class III beta-tubulin（＋）。提示肿瘤细胞向神经元和胶质成分双向分化。病理诊断幕上原始神经外胚层肿瘤。结论：节细胞胶质瘤可以出现胶质和神经成分的恶性转化。

Malignant Transformation of Anaplastic Ganglioglioma to Supratentorial Primitive Neuroectodermal Tumor： A Case Report and Literature Review

BACKGROUND ＆ OBJECTIVE： Anaplastic Gangliogliomas are rare tumors. Malignant progression almost invariably occurs in the glial component. To date, only a few cases with malignant transformation in both glial and neuronal components have been reported. In this article, we reported a case of anaplastic ganglioglioma with malignant transformation to supratentorial primitive neuroectodermal tumor 8 months after the initial diagnosis. METHODS：The primary and recurrent tumors were examined in histopathological characteristics and immunohistochemical staining. Literatures were reviewed. RESULTS： The initial diagnosis of anaplastic ganglioglioma in the left temporal lobe of an 8-year-old girl was confirmed by histopathology and immunohistochemistry. Under microscopy, the tumor was composed of a group of small cells with darknuclei and a group of moderate -sized cells with less-stained pleomorphic nuclei. In addition, some loose clusters of large tumor cells with abundant cytoplasm and vesicle nuclei tended to differentiate into neurons, while some others were differentiated ganglion cells. A significant increase in the reticulin staining was found. Immunohistochemistry showed tumor cells were focally positive for NSE, S-100 protein, Nestin, Vimentin, Desmin and GFAP. Similarly, those large tumor cells that differentiated to neurons were positive for both NSE and S-100 protein. Eight months after the initial diagnosis, left temporal tumor recurred. Histopathology revealed that in addition to the significant increased reticulin fibers, densely small to moderate tumor cells with more atypical nuclei and mitoses were found in the tumor, whereas no differentiated cells were seen. Immunohistochemistry demonstrated the expression of S-100 protein, NFP, Neuronal class Ⅲ beta-tubulin and GFAP in the tumor cells, indicating the simultaneous differentiation along neuronal and glial lines. The pathologic diagnosis of the recurrent tumor was supratentorial primitive neuroectodermal tumor. CONCLUSIONS： Cells in the recurre