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。     

Cystic partially differentiated nephroblastoma

Cystic partially differentiated nephroblastoma is a relatively rare tumour of the kidney usually affecting infants. Cystic Wilms’ tumour and multilocular cystic nephroma should be distinguished from cystic partially differentiated nephroblastoma. Multilocular cystic nephroma is a benign tumour whereas cystic Wilms’ tumour is at the malignant end of the range of classification of such tumours. Cystic partially differentiated nephroblastoma may undergo local recurrence but there is no report of metastasis.     

小儿肾母细胞瘤、神经母细胞瘤肿瘤组织培养的临床应用

目的：对比组织法与病理切片在肿瘤淋巴结转移的阳性率。方法：对14例肾母细胞瘤、6例神经母细胞瘤进行肿瘤组织、淋巴组织瘤旁培养，涂片进行病理诊断、并与传统的病理切片对比，结果：肿瘤组织培养与病理切片结果完全一致。对区域淋巴结转移的诊断，淋巴结组织培养优于病理切片，两者淋巴结转移的阳性率，肾母细胞瘤为66．6％（6／9）和33．3％（3／9）；神经母细胞瘤为50％（3／6）和33．3％（2／6），结论：淋巴结组织培养对肿瘤淋巴结转移的诊断率高于病理切片，对临床分期、治疗及预后判断具有重要的指导意义。     

A case of EMG (exomphalos, macroglossia, and gigantism) syndrome with associated renal tumor.

This is a brief report of a patient with Wiedemann-Beckwith syndrome and nephroblastoma with metastases, apparently cured by surgery, chemotherapy, and radiation.     

核仁组成区嗜银蛋白和增殖指数在肾母细胞瘤研究中的应用

目的 :研究肾母细胞瘤的组织学分型、临床分期与 DNA增殖指数及核仁组成区相关嗜银蛋白 ( Ag NOR)间的关系。方法 :通过流式细胞仪测定增殖指数 ( proliferating index,PI) ;用组织化学法检测 Ag NOR。结果 :正常肾脏与肾母细胞瘤组织间的 Ag NOR颗粒计数、颗粒直径及形状因子均有明显差异 ;间变型的 Ag NOR颗粒计数 ( 4 .2 )显著高于无间变型 ( 3.2 8) ;Ag NOR颗粒计数随分期增高而增高 ;高 Ag NOR计数组的 PI值 ( 4 4.35 )显著高于低 Ag NOR计数组 ( 32 .5 5 )。结论 :PI值及 Ag NOR计数可作为判断肾母细胞瘤增殖活性及预后的指标     

Neuropeptide Y receptors in renal cell carcinomas and nephroblastomas

Numerous peptide receptors are overexpressed in human cancer, permitting in vivo tumor targeting. Among such receptors, those for the neurotransmitter neuropeptide Y (NPY) are overexpressed in various tumors. Since NPY can play a role in the kidney, NPY receptor expression and/or endogenous production of peptides of the NPY family (NPY, PYY, PP) were evaluated in 40 renal cell carcinomas (RCCs) and 18 nephroblastomas. NPY receptor protein expression was investigated by in vitro autoradiography using (125)I-labeled PYY in competition with NPY receptor subtype-selective analogs. NPY, PYY and PP production was assessed immunohistochemically. Fifty-six percent of RCCs expressed the Y1 receptor subtype in moderate density, and 80% of nephroblastomas expressed Y1 and Y2 subtypes in moderate to high density. Y1 was also highly expressed in intratumoral blood vessels. In selected cases, NPY was observed in nerve fibers in close association with intratumoral blood vessels and in the vicinity of tumor cells, while no PYY or PP was detected immunohistochemically in these sites. NPY receptors on renal tumor cells and tumor blood vessels may therefore be the molecular targets of endogenous NPY released by intratumoral nerve fibers. With regard to clinical applications, NPY receptors may act as in vivo targets for receptor-directed therapy of RCCs and nephroblastomas for which alternative therapeutic approaches are still required.     

The efficacy and toxicity of SIOP preoperative chemotherapy in Malawian children with a Wilms tumour

Background

In Malawi, preoperative chemotherapy for Wilms tumour is a logical strategy, but detailed information on toxicity and efficacy in such a resource limited setting has been unavailable.

Procedure

Patients diagnosed with a unilateral Wilms tumour received preoperative chemotherapy—a two‐drug 4‐week regimen for localized disease and 6 weeks of a three‐drug regimen for metastatic disease. Estimated maximum tumour diameter, decrease in tumour size, resectability, stage distribution and haematological toxicity during therapy were documented.

Results

At diagnosis, 28% of 72 patients had an estimated maximum tumour diameter of more than 25 cm; 29% of patients had metastases. Eight children (11%) died during preoperative chemotherapy. More than half (59%) of the patients developed moderate neutropenia (neutrophils <1.0 × 10⁹/L; CTC grade 3) and 27% severe neutropenia (CTC grade 4 neutrophils <0.5 × 10.9/L). Grade 4 neutropenia occurred significantly more frequently in children receiving the three‐drug regimen compared to the two‐drug regimen; 50% (10/20) versus 15% (6/40) (P = 0.004). Fifty‐seven percent of all patients had CTC grade 4 anaemia (Hb < 6.5 g/dL) during treatment. Most tumours (92%, 56/61) showed a response to chemotherapy but 14% (8/58) remained unresectable.

Conclusion

Preoperative chemotherapy for Wilms tumour causes considerable haematological toxicity and treatment‐related mortality in malnourished Malawian children. A significant number of children have unresectable disease despite preoperative chemotherapy. To reduce treatment related mortality, consideration should be given to starting treatment with reduced doses in acutely malnourished patients. Pediatr Blood Cancer 2012;59:636–641. © 2012 Wiley Periodicals, Inc.