小儿恶性横纹肌样瘤33例临床病理分析

Malignant rhabdoid tumor of childhood:clinical and histopathological studies of 33 cases

目的探讨小儿恶性横纹肌样瘤(MRT)的临床病理特点、免疫表型、诊断与鉴别诊断。方法复习33例MRT的临床资料、组织切片,进行光镜检查和免疫组化染色。结果 33例MRT大部分为婴幼儿,肿瘤较大。其中肾14例,软组织11例,中枢神经系统8例。组织学特征是横纹肌样细胞和包涵体。免疫组化示CK、EMA和vimentin(+),INI1(-)。结论组织学上呈横纹肌样细胞,免疫组化CK、EMA和vimentin(+),INI1(-)是MRT诊断与鉴别诊断的关键。肿瘤高度恶性,需手术切除后辅以强力的化疗和放疗。

Objective To study the clinicopathologic characteristics, immunohistochemistry, diagnosis and differential diagnosis of malignant rhabdoid tumor （MRT） of childhood. Methods The clinical data, histopathologic pections and immunohistochemistry of 33 MRT cases were reviewed. Results There were 14 MRT cases in kidney, 11 cases in soft tissue, and 8 cases in central nervous system. The most cases were infancy and early childhood. The tumor size was usually large. Histological characteristics were rhabdoid cells and cytoplasmic inclusions. Immunohistochemically, CK, EMA and vimentin were positive; INI 1 was negative. Conclusion The histological features are rhabdoid cells, and the tumor cells express CK, EMA, and vimentin, but INI 1 is negative, which are the key to diagnosis and differential diagnosis. MRT is a highly malignant childhood neoplasm. The treatment is surgical resection followed by chemotherapy and radiation.