Unique Dermal and Subcutaneous Botryoid Rhabdomyosarcoma Associated with Mature Renal Tissue: Is this an Extrarenal Wilms' Tumor?

A unique dermal and subcutaneous botryoid rhabdomyosarcoma admixed with ectopic mature renal tissue, overlying the left lateral lumbosacral region of a 4-1/2-year-old girl is reported. The tumor was devoid of blastemal or immature epithelial elements and nephrogenic rests. The relationship of this lesion to an extrarenal Wilms' tumor with exclusive myogenous differentiation is discussed.     

Lumbosacral extrarenal Wilms' tumour: a case report and literature review

Occurrence of extrarenal Wilms' tumour (WT) is very exceptional and the diagnosis is almost always made after surgical intervention. The tumour can be located in the retroperitoneum, uterus, cervix, testes, skin and even in the thorax. The exact mechanism whereby a WT occurs in extrarenal tissues is not known. The presence of ectopic metanephric blastema cells or the WT gene that cause transformation of extrarenal primitive mesonephric or pronephric remnants into WT are both considered in the embryogenesis. Although ultrasonography and CT scan are both helpful in the definition of retroperitoneal tumours, there is no characteristic finding to diagnose an extrarenal WT before surgery. However the histological characteristics are the same as in intrarenal WT, a retroperitoneal teratoma should be clearly investigated for a possible admixture of WT cells. Patients with extrarenal WT are given the same treatment protocol as patients with stage III WT. In this paper, a 5-year-old female patient with an extrarenal WT located in the lumbosacral region is presented. Conclusion: as a rule, diagnosis of extrarenal Wilms' tumour is made after surgery. Surgical excision is the treatment of choice and the same general therapeutic rules should be followed as when the kidney were affected. Stage III guidelines for chemotherapy and radiotherapy are appropriate in these patients.     

Extrarenal Wilms' tumor.

Extrarenal Wilms' tumor is a rare entity usually seen as a mass in the retroperitoneal area. It may surround and distort otherwise normal kidneys and ureters. Like many other abdominal masses, its true nature remains uncertain until microscopic examination has been performed after surgery. The tumors appear to behave clinically like intrarenal Wilms' tumors, though in the cases reviewed there was a relatively higher incidence in older patients. The prognosis of extrarenal Wilms' tumor is difficult to evaluate due to the small numbers of cases reported and the differing tumor therapy used. However, those cases treated most recently appear to have a good response to therapy.     

Néphroblastome en sablier : une cause inhabituelle de compression médullaireDumbbell nephroblastoma: an uncommon cause of spinal cord compression

Rarely children with Wilms' tumor develop spinal cord dysfunction by metastatic spread into the epidural space or the cord parenchyma. In the case reported here, the mechanism of spinal compression was different. CASE REPORT: The authors report the clinical course of a 2-month-old boy with retroperitoneal extrarenal Wilms' tumor below the left kidney, characterized with a spinal cord compression developed through the intervertebral foramina. CONCLUSION: Abdominal tumor, usually corresponding to neuroblastoma, may be a nephroblastoma.     

Extrarenal nephroblastic proliferation in spinal dysraphism. A report of 4 cases.

Four cases of extrarenal nephrogenic proliferation in the sacrococcygeal region with spinal dysraphism are presented. In two of the cases, features of Wilm's or incipient Wilm's tumor were present. The previous literature on sacrococcygeal nephrogenic tissue is reviewed, and the impact of these findings on the histogenesis of extrarenal sacrococcygeal Wilm's tumor is discussed.     

肾母细胞瘤微卫星DNA变化分析

目的 研究分析１３例肾母细胞瘤（Ｗｉｌｍｓ肿瘤）患儿５个染色体点微卫星标记的变化。方法 ５个微卫星标记分别为：Ｄ７Ｓ１８０８、Ｄ９Ｓ１６１、Ｄ１２Ｓ１０５６、Ｄ１７Ｓ７９１和Ｓ２２Ｓ２７４,应用ＰＣＲ方法扩增Ｗｉｌｍｓ肿瘤组织ＤＮＡ,以该患儿正常组织作对照,扩增产物用含脲素的聚丙烯酰胺凝胶电泳及银染技术进行分析。结果 １３例Ｗｉｌｍｓ肿瘤患儿检测５条染色体５个位点的微卫星多态标记,只１例患儿７号染     

Inguinal Wilms' tumor (author's transl)]

Case report on a small inguinal Wilms' tumor in a 3-year-old boy. Their is strong evidence, that this heterotopic Wilms' tumor developed in dysplastic renal tissue.     

Extrarenal Wilm's tumour - a rare entity

A rare case of extrarenal Wilms' tumour (ERWT) that presented as an asymptomatic subcutaneous lumbar mass is reported. The diagnosis could only be established postoperatively.     

Immunohistochemical analysis of gamma catenin in Wilms' tumors

The aim of our study was to investigate the expression of gamma-catenin in normal kidney and in Wilms' tumor by immunohistochemistry and to correlate the results with tumor stage, histological type, and prognostic group. We investigated 28 cases of Wilms' tumor, 2 Wilms' tumor metastases in lungs, and 1 specimen of normal renal tissue. Expression of gamma-catenin was detected in 14 cases. There was a weak inverse relationship between gamma-catenin expression and tumor stage. Expression of gamma-catenin was detected in various histologic types of Wilms' tumor, but there was no statistically significant correlation, except in cases with diffuse anaplasia that were negative. In 2 metastatic cases and in the case of bilateral Wilms' tumor gamma-catenin immunostaining was not observed Our findings suggest an absence of strong correlation between the loss of gamma-catenin and unfavorable outcome.     

Glycosaminoglycan synthesis by Wilms' tumor.

Wilms' tumor contains approximately 1 mg hyaluronic acid and approximately 0.3 mg sulfated glycosaminoglycan per g tissue. Minced tumor and cells cultured from the tumor incorporate labeled acetate and glucosamine into hyaluronic acid and sulfated glycosaminoglycans. A particulate enzyme preparation derived from the tumor catalyzed the transfer of GlcUA or GlcNAc from UDP-GlcUA or UDP-GlcNAc at a rate of approximately 20 nmol/hr/mg protein to produce high molecular weight hyaluronic acid chains. The urine and plasma of a Wilms' tumor patient contained approximately 20 mg hyaluronic acid and 8 mg sulfated glycosaminoglycan/100 ml, respectively. It appears that this higher than normal level of circulating glycosaminoglycan is synthesized by the Wilms' tumor.     

Extrarenal Wilms' tumour

Extrarenal Wilms' tumour is rare and its imaging has received scant mention in the literature. We describe a 2-year-old boy with a firm mass in the right flank. CT, MRI and ultrasonography showed an inhomogeneous solid mass located in the retroperitoneum, which was separate from the right kidney. Angiography showed an enlarged right gonadal artery and irregularly tortuous vessels in the tumour similar to intrarenal Wilms' tumour (spider leg or creeping vine appearance). Histopathological examination confirmed an extrarenal Wilms' tumour.     

Molecular genetics of Wilms' tumour

Wilms' tumour, or nephroblastoma, is an embryonal malignancy of the kidney with an incidence of approximately 1 in 10000 live births. It occurs in both sporadic and familial forms, but only 1% of Wilms' tumour patients have a positive family history. The molecular genetics of Wilms' tumour have been the subject of extensive research and at least three genes ( WT 1, WT 2, WT 3) have been implicated. WT 1 has been mapped to 11p13, and it has been suggested that loss or inactivation of a tumour-suppressor gene at 11p13 might be a primary event in the development of Wilms' tumour. The WT 2 gene maps to 11p15 in the region of the Beckwith-Wiedemann locus. The WT 3 locus is likely to be located to chromosome 16q. The understanding of the molecular genetics of Wilms' tumour is reviewed briefly.     

Outcome of renal transplantation for Wilms' tumor and Denys-Drash syndrome: a report of the North American Pediatric Renal Transplant Cooperative Study

In some children with bilateral Wilms' tumor, reduction of tumor burden cannot be accomplished without total nephrectomy. In Denys-Drash syndrome, nephrectomy is required for associated Wilms' tumor or after progression to end stage renal disease secondary to diffuse mesangial sclerosis because of risk of development of Wilms' tumor. Current recommendation is to wait at least 1-2 yr after completion of chemotherapy for Wilms' tumor before renal transplantation. The North American Pediatric Renal Transplant Cooperative Study dialysis (1992-2001) and transplant registries (1987-2002) were analyzed, comparing children 0-18 yr old with Wilms' tumor and Denys-Drash syndrome to other primary diagnoses. There were 37 children with Wilms' tumor and 33 with Denys-Drash syndrome in the dialysis registry. Of these, 10 children with Wilms' tumor and three with Denys-Drash syndrome did not receive a renal transplant and all died. The cause of death was Wilms' tumor in eight children with Wilms' tumor and in one with Denys-Drash syndrome. The transplant registry included 43 children with Wilms' tumor, 43 children with Denys-Drash syndrome, and 7469 patients with other diagnoses. Acute rejection, graft and patient survival profiles from all three groups at 6 months, 1 and 3 yr post-transplant were comparable. There were no graft failures or deaths because of recurrent Wilms' tumor in the Drash group. There was one death with Wilms' tumor in the Wilms' group - a 2.5-yr-old child transplanted after 6 months of dialysis who died of Wilms' <6 months after renal transplantation. In conclusion, most children dialyzed because of Wilms' tumor and Denys-Drash syndrome who did not receive a renal transplant died of Wilms' tumor. However, the outcomes of children with Wilms' tumor and Denys-Drash syndrome who proceeded to renal transplantation are comparable with children with other diagnoses, with no graft failures because of recurrence and only one death from Wilms' tumor in a Wilms' patient who received only a short course of dialysis prior to transplantation. Current practices in children with Wilms' tumor and Denys-Drash syndrome appear to be on target to portend good outcome following renal transplantation.     

A novel WT1 gene mutation associated with wilms' tumor and congenital male genitourinary malformation

WT1 is located on the short arm of human chromosome 11 and consists of 10 coding exons. Mutations of this gene have been reported to be the cause of Wilms' tumor, congenital male genitourinary malformations, and/or renal disorders. We describe here a novel WT1 gene mutation, i.e. a point mutation at intron 7 (+2) in both the tumor and the germline cells of a patient with Wilms' tumor and congenital male genitourinary malformation, but without renal disorder. The position of the mutation is at a splice donor site of intron 7, which causes the splicing out of exon 7 and generates a truncated protein. This type of mutation in the WT1 zinc finger domain has not been reported before. The mutation is of paternal origin and is heterozygous in the germline cells. In the tumor cells, however, the maternal allele is largely lost, from 11p12 to 11p15, which results in maternal loss of heterozygosity. These results, together with the data from previous reports, suggest that WT1 may function in gonadogenesis, nephrogenesis, and Wilms' tumor tumorigenesis.     

Evidence for clonal development of Wilms' tumor.

To assess the clonality of Wilms' tumor, glucose-6-phosphate dehydrogenase (G6PD) enzymes were studied in normal and tumor tissue from 11 black girls who were heterozygous for G6PD. Normal tissues expressed both A and B type G6PD, whereas only a single G6PD enzyme was found in all tumor specimens. These data support the clonal nature of Wilms' tumor. In the one patient with bilateral disease, type B G6PD was found in both a recurrence and a subsequent tumor in the contralateral kidney. This finding is consistent with either the chance occurrence of the same G6PD in independent tumors or persistence of the original malignant clone. Another patient, who presented with the nephroblastomatosis complex (a precursor of Wilms' tumor), also had only type B enzyme detected. Further studies in patients with bilateral disease or the nephroblastomatosis complex, including the use of molecular biologic probes, are needed to test the hypothesis that Wilms' tumor in these cases arises from a somatic mutation as a second event in persons with an underlying genetic alteration.     

Diagnostic and therapeutic problems posed by malignant non Hodgkin lymphoma of renal origin in children. Apropos of 7 cases]

BACKGROUND. The kidneys of non Hodgkin lymphoma patients frequently contain lymphoma cells, but these tumors rarely arise in the renal tissue and are rarely located there. PATIENTS. A diagnosis of non Hodgkin lymphoma of renal origin or predominantly located in kidneys was made in 7 patients aged 2-14 years old. These patients formed part of a total of 450 patients with non Hodgkin lymphomas seen from 1974 to 1987. The first manifestation in these 7 children was an abdominal mass associated with hypertension in 3 cases; 2 of whom presented with acute kidney failure. Ultrasonography showed hypoechogenous masses in one (2 cases) or both kidneys (5 cases). The diagnosis of malignant lymphoma was made directly in only one patient who also presented with mediastinal and abdominal lymph node enlargement. In the others, the first diagnosis was Wilms tumor (5 cases) and polycystic disease of the kidney (1 case); the correct diagnosis of malignant lymphoma was later made from biopsies of renal (4 patients) or extrarenal involved tissue (2 patients). Six of the 7 cases were Burkitt lymphomas, and all 7 were in stage III (3 patients) and IV (4 patients). 6 patients (3 stage III and 3 stage IV) were successfully treated by chemotherapy with a median follow-up of 9 years. CONCLUSIONS. Differential diagnosis between non Hodgkin lymphomas of renal origin and a Wilms tumor may be difficult even though kidney failure is more frequent in lymphoma. Sonography is the best method for diagnosis showing typical hypoechogenous masses and diffuse homogeneous infiltration of the kidneys. In the absence of extrarenal (meningeal, testis, bone marrow) dissemination, definite evidence of lymphoma depends on the histological examination of tumoral tissue obtained by surgical biopsy.     

胎儿横纹肌瘤型肾母细胞瘤

目的 探讨胎儿横纹肌瘤型肾母细胞瘤（ＦＲＮ）特点和恰当的治疗方法。方法 从１９５５～１９９６年３６９例肾母细胞瘤中检出ＦＲＮ１０例。回顾性分析其临床表现、病理组织学特点和预后。结果 １０例ＦＲＮ均因腹部肿大或腹部肿物入院。经术前放、化疗肿瘤不缩小。６例单侧病变做瘤肾切除,５例获随访均长期存活。４例双侧病变中１例做双侧单纯肿瘤切除,３例做一侧瘤肾切除,对侧肾部分切除或单纯肿瘤切除,随访存活２年。结论     

Histology, fine structure and differentiation of experimental Wilms tumors (author's transl)]

Histologic studies indicate that the cycasin-induced Wilms' tumor in the rat is equal to human nephroblastoma in appearance. Therefore, it may represent an interesting system for experimental oncology. In electron microscopy, the spindle cells of the sarcoma region mostly represent tubular cells. Besides, the author's results showed that preexisting mesenchyma cells and blood vessels also form part of the tumor. Electron microscopy studies have shown that cycasin feeding will lead to early cellular changes indicating that cycasin exercises a nucleotoxic effect. Present results do not favor the dysontogenic concept of the formation of Wilms' tumor, since this tumor can be induced diaplacentally.     

Maturation of Pulmonary Metastases of Wilms' Tumor after Therapy: A Case Report

A case is reported of Wilms' tumor associated with multiple pulmonary metastases histologically showing maturation of the tumor cells at 9 years after the resection of the primary tumor and intensive therapy. A huge tumor of a 22-month-old patient's right kidney was resected. The tumor was diagnosed as Wilms' tumor of mesenchymal type (stage 1), which consisted of predominantly immature mesenchymal tissue including rhabdomyoblasts, smooth muscle and fibrous tissue, and few blastemal and epithelial components. Intensive preoperative and postoperative chemotherapy with actinomycin D and vincristine and postoperative irradiation therapy totaling 16 Gy were carried out. The patient was regularly followed up uneventfully until 9 years after the surgery. On routine chest x ray at the age of 10 years 11 months, multiple pulmonary nodules were found. The excised nodules from the bilateral lungs disclosed similar histology, exclusively composed of dense collagen bundles and fibrocytes intermingled with mature striated muscle bundles. No immature tumor components were detected. The possible effect of intensive therapy in this maturation was stressed, although spontaneous benign differentiation of tumor cells cannot be excluded.     

肾母细胞瘤术前化疗疗效与耐药性

目的：探讨肾母细胞瘤术前化疗疗效规律及耐药性的生物学特性,确认其术前化疗的合适疗程。方法：选择15例按L化疗方案接受术前化疗5周以上,资料记录完整的患儿作为术前化疗疗效研究对象,测量术前化疗不同疗程肿瘤大小;对18例未术前化疗和经不同疗程术前化疗病理档案,采用JSD－单克隆抗体对肾母细胞瘤组织多药耐药蛋白（P-glycoprotein,P-gp)进行免疫组织化学检测,了解P－gp在术前化疗不同疗程的 表达特点。结果：术前化疗2周后,肿瘤体积缩小值最明显,术前化疗4周后,其体积缩小值减缓,部分病例有逐渐增大趋势;而术前化疗疗程越长,肿瘤细胞P－gp表达越强。结论：L术前化疗方案对肾母细胞瘤的疗效肯定,疗程以2－3周后最显著。其疗效降低可能与术前化疗后瘤组织对化疗药物耐药性明显增强有关。合适疗程为3－4周。