伴有神经毡样岛的胶质神经元肿瘤四例报告及文献复习

Glioneuronal tumor with neuropil-like island： report of four cases and review of literature

目的探讨伴有神经毡样岛的胶质神经元肿瘤（GTNI）的临床病理特点。方法收集4例颅内和脊髓GTNI，其中3例为WHOIII级，1例原发为WHOII级复发后级别增高为WHOIII级，HE染色和免疫组织化学染色行组织形态学观察和病理分析，荧光原位杂交（FISH）检测肿瘤基因遗传学改变，并复习相关文献。结果组织形态学为弥漫增生的胶质细胞背景中散在大小不等的神经毡样岛结构，增生胶质细胞表现为星形细胞瘤或少突星形胶质细胞瘤特征；神经毡样细胞岛表现为大小不等、局灶性、界限清楚卵圆形的小岛，另见神经毡样基质内神经节样细胞。免疫组织化学染色显示，围绕形成神经毡样岛及神经毡样基质内神经节样细胞表达突触素和神经元核抗原，部分细胞表达少突胶质细胞转录因子2（Olig-2）；背景肿瘤细胞表达S．100蛋白、胶质纤维酸性蛋白、波动蛋白及Olig-2，部分病例p53阳性，阳性细胞数目为10％～50％；神经毡岛样结构区域Ki-67阳性指数〈3％，胶质细胞瘤区域不同级别不一样，低级别3％，高级别10％～25％。经FISH检测，4例均未见lp／19q及PTEN缺失，亦未见表皮生长因子受体扩增。结论GTNI多见于成人。1p／19q缺失不是GTNI的普遍基因学改变，仅见于极少数背景表现为少突胶质细胞瘤的病例。肿瘤预后与WHO分级有关，常出现局部复发，临床预后不好，尤其是脊髓GTNI，临床治疗建议进行肿瘤手术切除联合放化疗。

Objective To investigate the clinicopathologic features of glioneuronal tumor with neuropil-like island （GTNI）. Methods Four cases of intracranial and spinal GTNI, including three cases of WHO grade III, and one case of WHO grade II with grade III recurrence. HE and immunohistochemical （IHC） staining were used for pathologic analysis. Fluorescence in situ hybridization （FISH） was used to detect tumor genetic changes. Related literatures were reviewed. Results Microscopically, neuropil-like islands of varying sizes were seen within a background of glial proliferation, which showed features of astrocytoma or oligoastrocytoma. Neuropil-like islands were focal or circumscribed oval islands of varying sizes. Focally ganglion-like cells were seen. IHC staining revealed that in neuropil-like island area, the neuronal nuclei （Neu-N） as well as the cells around the neuropil-like island expressed oligodendrocyte lineage transcription factor-2 （Olig-2）, and synaptophysin. The background glioma cells expressed S-100, glial fibrillary acidic protein （ GFAP）, vimentin and Olig-2, and the number of p53 positive cells was 10% -50%. In the neuropil-like island area, the Ki-67 labeling index was less than 3%, while in the astrocytoma area it was around 10% -25%. By FISH testing, four cases were no deletion of 1p/19q and PTEN, also no amplification of epidermal growth factor receptor. Conclusions GTNI is more common in adults, 1p/19q deletions are uncommon in GTNI, only seen in a few cases with background oligodendroglioma. The prognosis is related to WHO grading. GTNI often recurs locally, and the prognosis is not good, especially in the spinal cord GTNI. The recommended treatment includes tumor resection combined with radiotherapy and chemotherapy.