胚胎发育不良性神经上皮瘤与皮质发育不良

目的观察胚胎发育不良性神经上皮瘤（DNT）的病理形态学及免疫组织化学特点,探讨其与皮质发育不良之间的关系以及组织来源。方法应用光镜和免疫组织化学EnVision法对14例DNT进行观察分析,并对患者进行长期随访。结果肿瘤位于颞叶的有11例,镜下由神经元和神经胶质成分混合构成,9例可见“特异的胶质神经元结构”。1例为简单型,8例为复杂型,5例为非特异型。11例标本充足的病例10例伴有皮质发育不良改变,表现为分子层和（或）白质内异位神经元数量增多（7例）,分子层内可见成行的外颗粒细胞层残留（4例）,脑皮质的结构异常（10例）,以及出现异常形态的神经细胞。免疫组织化学染色少突胶质样细胞（OLC）均呈现Olig2的免疫反应性,部分OLC表达nestin、微管相关蛋白2、神经丝蛋白、胶质纤维酸性蛋白,但神经元核抗原呈阴性。癫痫控制结果Ⅰ级12例,Ⅱ级2例,无肿瘤复发。结论DNT与皮质发育不良关系密切,应用免疫组织化学染色有助于DNT和皮质发育不良的诊断。

Dysembryoplastic neuroepithelial tumor: a clinicopathologic and immunohistochemical study

OBJECTIVE: To study the clinicopathologic features, immunophenotype and histogenesis of dysembryoplastic neuroepithelial tumor (DNT). METHODS: Fourteen cases of DNT were retrieved from the archival files of the Department. The histopathologic features and immunohistochemical findings were retrospectively studied. The long-term follow-up data were analyzed. RESULTS: Eleven of the 14 cases studied were located in the temporal lobe. Histologically, the tumor consisted of a heterogeneous admixture of neuronal and glial cells (including 1 simple form case, 8 complex form cases and 5 non-specific form cases). The specific glioneuronal element was seen in 9 cases. Variable degrees of cortical dysplasia (CD) were found in 10 out of the 11 cases which had sufficient tissue samples for thorough histologic examination. The morphologic appearance of CD included the presence of heterotopic neurons in molecular layer and/or white matter (7 cases), persistent subpial granular cell layer (4 cases), dyslamination (10 cases) and cellular abnormalities. Immunohistochemically, the oligodendroglial-like cells expressed Olig2. Some of which were positive for nestin, MAP-2, neurofilament and glial fibrillary acidic protein, but negative for NeuN. Long-term follow up revealed that 12 patients had class I postoperative seizure and 2 patients had class II seizure. No tumor recurrence was detected. CONCLUSIONS: DNT is frequently associated with CD. The morphologic diagnosis can be confirmed by immunohistochemical study using a panel of antibodies.