多形性黄色星形细胞瘤临床病理特点及免疫表型分析

Clinicopathologic and immunophenotyping study of pleomorphic xanthoastrocytoma

目的探讨多形性黄色星形细胞瘤(PXA)的临床病理特点及免疫表型。方法回顾性分析26例PXA的临床资料、影像学表现和病理组织学特点。运用HE染色及免疫组化EnVision法检测GFAP、vi mentin、EMA、S-100、NSE、Syn、NF、nestin、NeuN、CD68、CD34、EGFR、p53、Ki-67。观察其病理组织学特点和免疫表型特征,对所有病例进行随访。结果临床上主要表现为头痛和癫痫发作,影像示肿瘤均发生于大脑表浅部位,且伴有囊性变,增强后可见强化及瘤周水肿;典型组织形态学表现为瘤细胞呈多形性,可见黄色瘤细胞和嗜酸性小体(EGB)及核内包涵体,瘤组织内有多少不等的淋巴细胞散在浸润,有丰富的网状纤维,无坏死及血管内皮细胞增生,核分裂少或无。1例局灶区域出现上皮样结构,1例间变性PXA有较多核分裂,并见灶性坏死。免疫组化GFAP、vi mentin、S-100、NSE、nestin均阳性,p53、EGFR部分病例阳性,CD68散在瘤巨细胞阳性,Ki-67约1%瘤细胞阳性,EMA、CD34、Syn、NeuN、NF均阴性。随访无1例复发。结论 PXA是一种好发于年轻人的少见的具有特殊临床病理特征的、预后较好的中枢神经系统肿瘤。病理组织学上需与巨细胞型胶质母细胞瘤、脂质化胶质母细胞瘤、黄色瘤型脑膜瘤、胶质肉瘤和室管膜下巨细胞星形细胞瘤等鉴别。

Objective To study the clinicopathological features and immunophenotyping of pleomorphic xanthoastrocytoma（PXA）.Methods The data of 26 cases with PXA,including clinical manifestation,imaging features and pathology finding were analyzed retrospectively.The characteristcs of histopathology and immunophenotypes were studied by haematoxylin and eosin（HE） stain and immunohistochemical stain.The follow-up data were analyzed.Results The most frequent presentations included headache and seizures.Radiology revealed PXA located in superficial cerebral hemisphere and cystic change.Cyst wall enhancement and pretumoral edema were also found.Typical histologic features included marked cellular pleomorphism with xanthomatous cell.Eosinophilic granular bodies,intranuclear cytoplasmic inclusion,lymphocytic infiltrates and rich reticulin were seen in almost all cases.Necrosis and endothelial proliferation were absent.No or rare mitoses.One case featuring epithelioid pattern in focal area and one case featuring mitotic activity and focal necrosis were diagnosed as anaplastic PXA.Positive immunoreactivity was in glial fibrillary acidic protein（GFAP）,vimentin,S-100,neuron-specific enolase（NSE） and nestin.Some cases were positive for p53 and EGFR,CD68 immunostaining usually detected only a few giant cells.The positive cells for Ki67 about 1%,immunostaining to EMA,CD34,synaptophysin（Syn）,NeuN,neurofilaments（NF） was negative.No cases had recurrence after total resction.Conclusion PXA is a rare tumor of central nervous system in young adults with specific clinicopathologic features and favorable prognosis.Histologically,PXA should be differentiated from giant cell glioblastoma,lipidized glioblastoma,xanthomatous meningioma,gliosarcoma and subependymal giant cell astrocytoma.