中枢神经系统非典型畸胎瘤样/横纹肌样瘤临床病理特点

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)的临床病理特征、组织发生及预后。方法应用光镜、特殊染色及免疫组化染色观察1例2岁儿童大脑AT／RT的病理组织学特点，结合国内外文献进行讨论。结果肿瘤含有横纹肌样细胞、原始神经外胚层、上皮及间叶多向分化成分。肿瘤中网状纤维丰．富。免疫组化染色Vim、EMA、CKpan、GFAP、Syn及CgA均呈阳性表达，PLAP、CD117、SMA及：NF?呈阴性反应。结论AT／RT为发生在儿童中枢神经系统罕见的高度恶性肿瘤，多数患者1年内死亡。肿瘤极易误诊为髓母细胞瘤、原始神经外胚叶肿瘤(PNET)、脉络丛乳头状癌及生殖细胞肿瘤。免疫组化染色对确诊AT／RT十分重要。本瘤的组织发生仍不清楚。

Clinicopathological features of atypical teratoid/rhabdoid tumor of the central nervous system

Purpose To investigate the clinicopathological features, histogenesis and prognosis of atypical teratoid/rhabdoid tumor (AT/RT) of the central nervous system (CNS) . Methods A case of the cerebral AT/RT occurring in a 2-year-old child was observed by light microscopy, special stain and immunohistochemistry. The clinical and pathological features in this case and in the literature were discussed. Results The tumor containing rhabdoid cells, variable components of primitive neuroectodermal, epithelial and mesenchymal components. Reticulin was abundant in many of tumor tissues. Immunohistochemical study demonstrated strong positivity for vimentin, EMA, CKpan, GFAP, Syn and CgA, and negative for PLAP, CD117, SMA and NF. Conclusions AT/RT is a malignant embryonal CNS tumor manifesting in chirldren . The most patients died within 12 months after diagnosis . The tumors are often misdiagnosed as medulloblastoma, primitive neuroectodermal tumor (PNET), choroid plexus carcinoma or germ cell tumors. The importance of immunohistochemical studies for making a correct dignosis is emphasized. The histogenesis of tumor remains unclear.