250例难治性癫痫相关肿瘤的临床病理学特征及BRAF V600E突变分析

BRAF V600E mutation and clinicopathologic characteristics in 250 cases of brain tumors associated with epilepsy

目的探讨难治性癫痫相关肿瘤的临床病理学特征及BRAFV600E突变特点。方法收集2008年3月至2017年8月之间，首都医科大学三博脑科医院功能神经科诊断明确的癫痫相关肿瘤病例250例，对患者的临床、病理资料进行回顾性总结，并对部分病例BRAFV600E突变进行检测和分析。结果250例手术患者中男132例，女118例，男女比约1．1：1．0。发病年龄2-67岁，平均年龄22岁。影像学均显示为占位性病变，颞叶累及最为多见（44．4％，111／250）。肿瘤类型包括5类，其中节细胞胶质瘤（GG）占58．4％（14/250），胚胎发育不良性神经上皮性肿瘤（DNT）占24．O％（6/250），多形性黄色星形细胞瘤（PXA）占12．8％（3/250），血管中心性胶质瘤（AG）占4．0％（1/250），乳头状胶质神经元肿瘤（PGNT）占0．8％（2／250）。其中9例GG混合PXA或DNT样形态结构，35例合并局灶性皮质发育不良（FCD）。对74例GG及28例PXA进行BRAFV600E基因测序检测，GG中突变率为58．1％（43／74），PXA中为46．4％（13／28）。GG、DNT、AG及PGNT多为WHO分级Ⅰ级。其中GG病例中有34例存在不同程度的WHOⅡ／Ⅲ级肿瘤增殖活跃区。PXA多数为WHOⅡ级，9例病例存在不同程度WHOⅢ级的问变性肿瘤细胞区。结论难治性癫痫相关的脑肿瘤以低级别混合性神经元．胶质肿瘤为主，其中GG最多见：该类肿瘤可发生于中枢神经系统的任何部位，以颞叶多发；每种肿瘤都有其独特的组织形态学结构，但少数肿瘤形态学较为复杂，可以存在2或3种成分的混杂。BRAF V600E在GG及PXA中存在很高比例的突变率．对肿瘤的诊断及治疗有着重要的指导意义。

Objective To investigate the clinicopathologic characteristics and BRAF V600E mutation of brain tumors associated with epilepsy. Methods Totally 250 patients with brain tumors associated with epilepsy were included from March 2008 to August 2017 retrospectively at Sanbo Brain Hospital, Capital Medical University. The clinical manifestations, histological features and BRAF V6OOE mutation results were collected and analyzed. Results There were 132 males and ll8 females, and the male to female ratio was 1.1 ： 1.0. The age of patients ranged from 2 to 67 years （ mean 22 years ）. The tumors had obvious local space occupying effect on MRI. The temporal lobe was the most common site （44. 4%, 111/250） . There were 58.4% （146/250） of ganglioglioma （GG） , 24. 0% （60/250） of dysembryoplastic neuroepithelial tumor （ DNT ）, 12. 8% （ 32/250 ） of pleomorphic xanthoastrocytoma （PXA） , 4. 0% （10/250） of angiocentric glioma （AG） and 0. 8% （2/250） of papillary glioneuronal tumor （PGNT）. Mixed GG, PXA and DNT morphological structures were found in 9 of patients. Among 250 cases,35 cases were accompanied by focal cortical dysplasia（FCD）. BRAF V600E was seen in 43 of 74 （58.1%） GG and 13 of 28 （46.4%） PXA. The most common pathologic grade of GG, DNT, AG and PGNT was WHO I. Some of the tumor cells from GG （ 34 cases） showed higher proliferative activity （ WHO Ⅱ/Ⅲ）. Most cases of PXA were WHOⅡ and high proliferative activity was seen in nine cases.Conclusions The association of low-grade glioneuronal tumors with intractable epilepsy was well-recognized. The most common low-grade glioneuronal tumors were GG. GG may occur in any part of the central nervous system, with a predilection for temporal lobe. Each type of low-grade glioneuronal tumors has its own unique histological morphology, but some may show complex features with 2 or 3 mixed components. The occurrence of BRAF V600E mutations in GG is common, and their detection may be valuable for the diagnosis and treatment in GG.