摘要： 目的 观察伴间变特征的多形性黄色瘤型星形细胞瘤的组织病理学特征。方法与结果 女性患者，58 岁。头部MRI 显示右侧颞叶和基底节区不规则长T1、长T2 信号，边界清楚，周围脑组织水肿不明显；脑桥和右侧侧脑室受压、中线结构向左侧偏移；增强扫描病灶呈多发团块状和斑片状明显强化。组织学观察肿瘤细胞呈多形性，由单核细胞或多核瘤巨细胞、泡沫样肿瘤细胞和梭形细胞混合构成，可见嗜酸性小体和核内包涵体；部分区域肿瘤细胞密集，细胞异型性明显，核质比增高。肿瘤细胞胶质纤维酸性蛋白、波形蛋白、S-100蛋白、神经元核抗原和P53蛋白表达阳性；突触素、嗜铬素A、神经微丝蛋白、CD34 和异柠檬酸脱氢酶1 表达阴性；Ki-67 抗原标记指数约为8.20%。结论 伴间变特征的多形性黄色瘤型星形细胞瘤临床罕见，影像学表现对诊断有一定提示意义，明确诊断仍依赖特征性的组织形态学特征和免疫学表型。

关键词: 星形细胞瘤, 间变, 病理学, 免疫组织化学

Abstract: Objective  To investigate the clinicopathological features of pleomorphic xanthoastrocytoma with anaplastic features (PXA-A).  Methods  The clinical manifestations, imaging, histopathological features, and immunophenotype were analyzed in one case of PXA-A, and relevant literatures were reviewed. Results  The patient was a 58-year-old woman. MRI examination revealed a parenchyma mass with irregularly long T1 and long T2 signal in right temporal lobe and basal ganglia region. The border was clear and peritumoral edema was inconspicuous. The mesocephalon and right ventricle were compressed, and the midline was shifted to left. Enhanced MRI showed multiple flaky and nodular enhancement. Histologically, tumor cells showed remarkable cellular pleomorphism, and they were composed of mononuclear cells, multinuclear giant tumor cells, frothy tumor cells and spindle cells. Eosinophilic granular bodies and intranuclear inclusions were seen. Tumor cells in partial regions were intensively arranged, with obvious atypia. Immunohistochemical analysis showed immunoreactivity of the cells to glial fibrillary acidic protein (GFAP), Vimentin (Vim), S-100 protein (S-100), neuronal nuclei (NeuN) and P53. The cells showed a negative reaction for synaptophysin (Syn), chromogranin A (CgA), neurofilament protein (NF), CD34 and isocitrate dehydrogenase 1 (IDH1). The Ki-67 label index was 8.20% .  Conclusions  PXA-A is a rare tumor. The imaging features can offer a few diagnostic cues. However, a definite diagnosis depends on the histological and immunohistochemical features.

Key words: Astrocytoma, Anaplasia, Pathology, Immunohistochemistry