伴WAGR综合征的肾母细胞瘤临床病理观察

Nephroblastoma with WAGR syndrome:a clinicopathologic analysis

目的探讨伴WAGR综合征的肾母细胞瘤的基本病理形态特点及临床特征。方法1例伴WAGR综合征的肾母细胞瘤病例,分析其病理形态、免疫表型、WT1(11p13)基因缺失情况及临床特点,并复习相关文献。结果一岁男性患儿,右肾肿瘤,肿瘤大小8.1 cm×6.7 cm×3.6 cm。肿瘤镜下形态以梭形细胞为主,部分细胞轻度异型,可见少量不同成熟程度的小管状结构,仅见小灶疑似胚芽细胞;免疫组化Ki-67阳性指数5%,肿瘤细胞Vimentin(+)、SMA(+)、Desmin(+),WT-1(-);FISH检测WT1(11p13)基因缺失。结论肾母细胞瘤经化疗后,胚芽细胞可减少、消失,或进一步向成熟的上皮和间叶成分分化,充分取材仍未查见明确胚芽细胞,且WT-1阴性,不能轻易除外肾母细胞瘤,需结合临床病史、并借助分子手段进一步明确。

Objective To investigate the pathological and clinical features of nephroblastoma with WAGR syndrome.Methods Morphological observation,immunohistochemistry and fluorescence in situ hybridization(FISH)for detecting deletion of WT1(11P13)were applied in a case of nephroblastoma with WAGR syndrome.The clinical features and relevant literatures were also reviewed.Results A 1-year-old boy presented with a neoplasm in the right kidney,which measured 8.1 cm×6.7 cm×3.6 cm.The tumour was composed of fusiform cells mostly.And mild cytologic atypia could be observed in some tumour cells.Tubular structures differentiating to various degrees were found occasionally.Only small foci were suspected as blastemal cells.Immunohistochemical staining showed the tumor cells were positive for Vimentin,SMA,Desmin,but negative for WT-1.Ki-67 index was about 5%.Deletion of WT1(11p13)gene was detected by FISH.Conclusion Chemotherapy-induced changes include necrosis of tumour cells,maturation of blastemal,epithelial,and stromal components.Nephroblastoma should not be excluded easily,although blastemal cells have not been identified decidedly and tumour cells are negative for WT-1.Clinical data and molecular techniques play an important role in the diagnosis.