中枢神经系统非典型畸胎瘤样/横纹肌样瘤10例临床病理分析

Atypical teratoid/rhabdoid tumor of the central nervous system:a clinicopathological analysis of 10 cases

目的探讨中枢神经系统非典型畸胎瘤样/横纹肌样瘤(atypical teratoid/rhabdoid tumor,AT/RT)的临床病理学特征、诊断、鉴别诊断及预后。方法回顾性分析2016年~2019年中南大学湘雅医院诊治的10例AT/RT的临床、影像学及病理学特征,并对其进行随访及相关文献复习。结果10例患者发病年龄1~6岁,中位年龄2.5岁,临床以呕吐、行走不稳为主要症状。肿瘤发生部位:小脑2例,脑室5例,额顶叶3例。MRI检查示肿瘤呈占位性病变,部分囊性变伴出血,增强扫描后均有不规则或不均匀强化。镜下见肿瘤细胞呈多形性,有梭形细胞、小圆细胞及中等大小多边形或圆形细胞,区域可见典型的横纹肌样细胞,部分围绕血管排列,部分富有黏液样背景,有不同程度的坏死,病理性核分裂象易见;肿瘤细胞呈多向分化。免疫表型:Olig2、p53、GFAP、EMA、Syn、vimentin、CD99呈阳性,10例均有特征性的INI1蛋白表达缺失。7例获得随访资料,3例失访,中位生存时间为5.8个月。结论AT/RT属于罕见的中枢神经系统恶性胚胎性肿瘤,呈侵袭性生长,组织学形态呈多形性,并且具有特征性的分子遗传学改变,放、化疗治疗效果不佳,预后差。

Purpose To investigate the clinicopathological features,histological classification,immunophenotype,differential diagnosis and prognosis of atypical teratoid/rhabdoid tumor in the central nervous system.Methods 10 patients with atypical teratoid/rhabdoid tumor diagnosed in Xiangya Hospital of Central South University were collected from 2016 to 2019.The clinical,imaging and pathological features of 10 atypical teratoid/rhabdoid tumor were observed,and the follow-up and literature review were conducted.Results The ages of patients were 1-6 years old and the median age was 2.5 years.The main clinical symptoms were vomiting and walking instability.The tumors occurred in the cerebellum in 2 cases,the ventricle in 5 cases,and the frontal parietal lobe in 3 cases.MRI showed that space occupying lesions,some cystic changes accompanied with hemorrhage,and irregular or uneven enhancement after enhanced scanning.Histologically,the tumor cells were pleomorphic,with spindle cells,small round cells and medium-sized polygonal or round cells.Typical rhabdomyoid cells were found in some region.The tumor cells were arranged around the blood vessels,some were rich in mucinous background,with varying degrees of necrosis,and pathological nuclear mitosis was easy to see.Immunohistochemical staining showed multi-directional differentiation that the expression of Olig2,p53,GFAP,EMA,Syn,vimentin,CD99 were positive,and INI1 protein was absent in all cases.7 cases were followed up and 3 cases were lost.The median survival time was 5.8 months.Conclusion Atypical teratoid/rhabdoid tumor is a rare malignant embryonal tumor of the central nervous system.It is characterized by invasive growth,pleomorphic histology,and characteristic molecular genetic changes.The therapeutic effect and the prognosis are poor.