Dysembryoplastic neuroepithelial tumour (DNT). Is the mechanism of seizures related to glutamate? An immunohistochemical study.
Dysembryoplastic neuroepithelial tumour (DNT). Is the mechanism of seizures related to glutamate? An immunohistochemical study.
复制标题
胚胎发育不良性神经上皮肿瘤（DNT）。
作者：
D. Adamek;A. Korzeniowska;R. Morga;P. Lopatka;I. Jeleńska;B. Danilewicz
胚胎发育不良性神经上皮肿瘤（DNT）是一种罕见的低度、混合性神经元和神经胶质肿瘤，通常与儿童时期的顽固性、复杂的部分或全身癫痫发作有关。手术后预后良好。我们提出了一个典型的案件发生在一个18岁的男性，谁提出了简单的部分性癫痫发作没有迹象表明颅内压升高。CT和MR显示病灶位于右侧颞叶。组织学上发现了典型的DNT结构的特征，具有混合细胞组成。对手术的反应非常好。肿瘤没有复发，癫痫控制仍然良好。谷氨酸受体GluR-2的免疫组化显示较强的免疫阳性神经元内的肿瘤，尤其是在边缘的病变相比，明显正常的大脑皮层。兴奋性氨基酸转运蛋白EAAT 1和EAAT 2的表达均较正常皮质弱，且表达不均匀。这也许可以解释癫痫发作的机制（升高的多巴胺能刺激），并可能提示神经元的兴奋性毒性损伤。
Dysembryoplastic neuroepithelial tumour (DNT) is a rare low-grade, mixed neuronal and glial tumour, usually associated with pharmacologically intractable, complex partial or generalised seizures which date from childhood. The prognosis after surgery is favourable. We present a classic case of DNT occurring in an 18-year-old male, who presented simple partial seizures without signs of raised intracranial pressure. CT and MR demonstrated focal mass located in the right temporal lobe. Histologically there were found the features of a typical DNT architecture with mixed cellular composition. The response to surgery was excellent. The tumour has not recurred, and the control of seizures remained good. Immunostaining for glutamate receptor GluR-2 showed stronger immunopositivity in neurones dispersed within the tumour and especially in margins of lesion as compared with apparently normal cerebral cortex. The expression of both excitatoryamino acid transporterproteins EAAT1 and EAAT2 was weaker then in normal cortex and uneven. This perhaps may explain the mechanism of seizures (elevated glutaminergic stimulation), and may suggest the excitotoxic damage of neurones.