Anaesthetic management of a patient with the intracardiac extension of Wilms' tumour

Summary Wilms' tumour (nephroblastoma) is known to invade the inferior vena cava and extend to the intracardiac chambers. We describe the treatment and surgical removal of the intracardiac extension of a Wilms' tumour using cardiopulmonary bypass in a 4-year-old girl. Techniques to avoid paradoxical embolism in the presence of a patent foramen ovale and to deal with excessive hepatic venous blood flow using the Pringle manoevre (hepatic inflour occlusion) are described. Good communication between anaesthesiologists, surgeons and perfusionists was indispensable. The anaesthesiologist is an important member of the team during performance of a complicated procedure.     

Myogenesis in Wilms Tumors Is Associated with Mutations of the <Emphasis Type="Italic">WT1</Emphasis> Gene and Activation of Bcl-2 and the Wnt Signaling Pathway

Wilms tumors with WT1 mutations [WT1(–)] have a stromal-predominant histology with varying extents of rhabdomyogenesis. These tumors also frequently have mutations in the beta-catenin gene (CTNNB1). We have investigated the molecular events that may explain the origins of rhabdomyogenesis in WT1(–) tumors. Of 35 Wilms tumors, we identified 12 with WT1 mutations, of which 9 carried CTNNB1 mutations. We compared WT1 wild-type tumors [WT1(+)] with WT1(–) tumors for histological features, localization of beta-catenin, Bcl-2 expression, and apoptosis using an in-situ end-labeling technique. WT1(+) tumors showed triphasic and blastemal- and epithelial predominant-histology. Expression of WT1, beta-catenin, and Bcl-2 recapitulated those of normal kidney epithelial development. Localization of beta-catenin was observed in the cytoplasm and cytoplasmic membrane of early glomerular epithelial structures. Bcl-2 is also expressed in condensing blastema and early glomerular epithelial structures which had little apoptosis. WT1(–) tumors, regardless of whether CTNNB1 mutations were detected or not, showed a stromal-rich phenotype with abundant expression of beta-catenin in the nucleus of the rhabdomyoblasts. Bcl-2 was expressed in rhabdomyoblasts, but not in blastemal cells undergoing apoptosis, suggesting that WT1 regulates Bcl-2 positively in the epithelial pathway, but negatively in the myogenic pathway. These data indicate that mutations in WT1 might alter the Wnt signaling pathway and Bcl-2 related-apoptosis. In WT1(–) tumors, the nuclear accumulation of beta-catenin and Bcl-2 expression are associated with rhabdomyogenesis, and dysregulation of Bcl-2 may be a mechanism by which the histogenesis (loss of blastemal component, muscle differentiation) may be explained.     

Repeated surgical excision for an unusual variant of nephroblastoma: case report and review of the literature

Bilateral fetal rhabdomyomatous nephroblastoma is a rare variant of Wilms' Tumor. The authors report the evolution over 48 months of a 10-month-old baby with bilateral nephroblastoma for which a left nephrectomy was initially performed. A right kidney tumor was enucleated preserving the kidney. The transformation of the primary tumor into a completely differentiated cystic nephroblastoma or nephromalike tumor and the appearance of a metachronous lesion was seen. This report emphasizes the role of nephron-sparing surgery in bilateral Wilms' Tumor when a benign transformation occurs under chemotherapy.     

Wilms' tumor: transureteral intravesical extension and presentation as urinary retention

The authors report an unusual case of Wilms’ tumor. The tumor grew transureterally into the urinary bladder, became dislodged, and presented as recurrent urinary infection with retention of urine after the child underwent nephroureterectomy. Such a presentation has not been reported earlier.     

Panlobar nephroblastomatosis: a distinctive form of renal dysplasia associated with Wilms'' tumour

An increasing variety of dysplastic lesions of metanephric origin ('the nephroblastomatosis complex') have been recognized as precursors of Wilms' tumour. We describe here four cases of a hitherto unrecognized renal dysplasia associated with Wilms' tumour and having a panlobar distribution. It has many features in common with the intralobar form of nephroblastomatosis, but differs in extending through the full thickness of the renal substance from calyx to capsule. These cases are also characterized by an increased proportion of well-differentiated tissue elements and by the presence, in some cases, of anomalous metanephric differentiation in the pericalyceal tissues or renal capsule. The presence of Wilms' tissue arising deep in the renal substance should alert the pathologist to make a thorough search for associated dysplastic elements in the kidney.     

肾母细胞瘤的诊治分析

[目的]探讨儿童肾母细胞瘤诊治方法,为改善其预后提供经验.[方法]回顾性分析本院收治的肾母细胞瘤40例,由小儿外科、小儿内科(肿瘤组)、病理科、放射诊断治疗科联合诊断,39例实施手术、化疗及放疗等方法综合治疗.Ⅰ期及Ⅱ期预后良好型不放疗,手术切除肿瘤有困难或存在远隔转移的Ⅲ、Ⅳ期患儿进行术前化疗4～6周.[结果]全组40例,分期:Ⅰ期4例;Ⅱ期21例;Ⅲ期6例;Ⅳ期7例;Ⅴ期2例.分型:预后良好型28例,预后不良型8例,透明细胞肉瘤型3例,横纹肌样瘤型1例.随访34例,28例获得完全缓解(71.8%),目前持续完全缓解25例(64.1%).无瘤生存率为64.1%(25/39),生存时间为6～153个月.6例未获得缓解者均死于疾病进展,无治疗相关性死亡.[结论]多学科联合诊断、综合治疗肾母细胞瘤可以取得良好疗效.手术是根本的治疗方法,切除肿瘤有困难或存在远隔转移的中晚期患者术前化疗数周,可降低手术风险、提高肿瘤切除率.术后标准化疗对于肾母细胞瘤的预后至关重要.     

Multifocal metanephric adenoma in childhood

Metanephric adenoma is the most commonly occurring member of the metanephric tumor family, which also includes metanephric adenofibroma and metanephric stromal tumor. According to the World Health Organization classification, however, it is not commonly multifocal. Reported herein is the case of a 9-year-old boy with multifocal metanephric adenoma. Histologically, surgical sections showed multifocal proliferation of small rounded and uniform cells with smooth nuclear contours, scant pale-staining cytoplasm, dark-staining nuclei, and inconspicuous nucleoli: the cells were arranged in sheets and acinal, ductal, glomeruloid, and papillary structures. On immunohistochemistry the tumor cells were positive for vimentin, cytokeratins (CAM5.2, AE1/AE3, and CK18), and WT1, but negative for cytokeratin 7 (CK7) and epithelial membrane antigen (EMA). The Ki-67 labeling index was <1%. In addition, cytogenetic analysis indicated a normal karyotype (46XY). Other histologically similar tumors are papillary renal cell carcinoma and nephroblastoma, and it is necessary to distinguish metanephric adenoma from those tumors because of malignancy. In contrast to those tumors, metanephric adenoma has inconspicuous nucleoli, loss of CK7 and EMA expression, and no mitotic figures. Thus, the histological and immunohistochemical features of the present case were compatible with metanephric adenoma.     

nov基因在不同种属动物脊髓中的表达

用地高辛标记的cRNA探针原位杂交方法研究了鲢、青蛙、蛇、鸡、牛、犬和猫脊髓中肾母细胞瘤过度表达基因（nov）mRNA阳性神经元的种系发育。结果显示，低等脊椎动物鲢、青蛙和蛇脊髓中仅有少量novmRNA阳性神经元，分布于灰质腹角。鸡脊髓中阳性神经元除主要分布于脊髓腹角外，中央灰质也有少量分布。哺乳动物牛、大和猫脊髓灰质中novmRNA阳性神经元分布广泛，背腹角、中央灰质及中央核区都检测到很强的杂交信号。以上结果表明，nov基因在从低等脊椎动物到高等脊椎动物的进化过程中非常保守，这种保守性提示nov基因在脊髓神经元发育、分化及正常生理功能中可能具有重要作用。