Deb P, Sharma M C, Tripathi M, Sarat Chandra P, Gupta A, Sarkar C
Department of Pathology, All India Institute of Medical Sciences (AIIMS), New Delhi, India.
Neuropathol Appl Neurobiol. 2006 Oct;32(5):461-8. doi: 10.1111/j.1365-2990.2006.00734.x.
The spectrum of glioneuronal lesions underlying intractable epilepsies includes malformative pathologies like focal cortical dysplasia (FCD); and neoplastic lesions like gangliogliomas (GG) and dysembryoplastic neuroepithelial tumours (DNT). These may occur either singly or as dual lesions, having simultaneous presence of both elements. Currently, the relationship between the malformative and neoplastic glioneuronal lesions is poorly understood. Recently, CD34, a stem cell marker transiently expressed during early neurulation, has been identified in these tumours. This study was undertaken to (i) evaluate the role of CD34 as a diagnostic marker for glioneuronal lesions of epilepsy, namely, GG, DNT and FCD, and (ii) attempt to define the relationship among these lesions, using CD34 as a marker. Tissues resected from 47 patients with intractable epilepsy due to glioneuronal lesions (GG, FCD, DNT) were studied. These were evaluated for CD34 expression, using immunohistochemistry. Dysplastic or atypically differentiated neural precursors which could not be identified on routine haematoxylin and eosin (H&E) staining were highlighted by CD34 immunostaining. The pattern of immunostaining was diffuse in GGs, unlike FCDs, wherein cells were present singly or in small clusters. However, cases of DNT and control tissue were largely CD34-immunonegative. Based on these findings, we propose a possible common origin of GG and FCD, from a bipotent precursor that undergoes abnormal glioneuronal development, while DNTs possibly have a different origin. The CD34-immunoreactive cells represent dysplastic or undifferentiated neural precursors, which may signify a valuable marker for the diagnostic evaluation of neoplastic and/or malformative pathologies in patients with intractable epilepsy.
难治性癫痫所涉及的神经胶质神经元病变谱包括发育异常性病变，如局灶性皮质发育不良（FCD）；以及肿瘤性病变，如神经节胶质瘤（GG）和胚胎发育不良性神经上皮肿瘤（DNT）。这些病变可能单独出现，也可能以双重病变形式出现，即同时存在这两种成分。目前，发育异常性和肿瘤性神经胶质神经元病变之间的关系尚不清楚。最近，在这些肿瘤中发现了CD34，一种在早期神经胚形成过程中短暂表达的干细胞标志物。本研究旨在：（i）评估CD34作为癫痫神经胶质神经元病变（即GG、DNT和FCD）诊断标志物的作用；（ii）以CD34作为标志物，试图明确这些病变之间的关系。对47例因神经胶质神经元病变（GG、FCD、DNT）导致难治性癫痫的患者切除的组织进行了研究。采用免疫组织化学方法评估这些组织中CD34的表达情况。CD34免疫染色突出显示了常规苏木精和伊红（H&E）染色无法识别的发育异常或非典型分化的神经前体细胞。与FCD不同，GG的免疫染色模式为弥漫性，FCD中的细胞单个或成小簇存在。然而，DNT病例和对照组织大多为CD34免疫阴性。基于这些发现，我们提出GG和FCD可能有共同起源，源自经历异常神经胶质神经元发育的双能前体细胞，而DNT可能有不同起源。CD34免疫反应性细胞代表发育异常或未分化的神经前体细胞，这可能是难治性癫痫患者肿瘤性和/或发育异常性病变诊断评估的一个有价值的标志物。
