1/19. Malignant rhabdoid tumor of soft tissues: a cytopathological and immunohistochemical study.We describe the cytopathological and immunohistochemical features of a primary malignant rhabdoid tumor (MRT) located in the left forehead region of an 8-mo-old female. The cardinal characteristics are hyaline cytoplasmic inclusions, rounded or bean-shaped nucleus, vesicular chromatin, central prominent nucleolus, and poorly defined cytoplasmic profile. Both the cytoplasm and the hyaline inclusion are vimentin and keratin positive, but negative with desmin, S-100 protein, neuron-specific enolase, (NSE) myoglobin, leukocyte common antigen (LCA), and alpha-1-antichymotrypsin. This immunohistochemical pattern, although not exclusive to MRT, is fairly typical of MRT, and when it is assessed in conjunction with cytopathological findings and clinical data permits a confident diagnosis of MRT. We emphasize the utility of immunohistochemical techniques in making the differential diagnosis of MRT against other childhood round-cell tumors.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
2/19. rhabdoid tumor of the skin.A tumor in the skin of a 42-year-old man was analyzed by light and electron microscopic study and immunohistochemistry. The tumor cells were large and contained eosinophilic, periodic acid-Schiff (PAS)-positive inclusions in the cytoplasm. Immunohistochemically, the neoplasm was positive for intermediate filaments, cytokeratin, vimentin, desmin, and alpha-1-antichimotrypsin, and negative for S-100 and leukocyte common antigen (LCA). Ultrastructurally, the cytoplasm and cellular processes of the cells were inundated with intermediate filaments, some of which were tightly bundled. Junctional complexes and secretory granules were absent. These features suggest a rhabdoid tumor: a malignant tumor of uncertain origin.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
3/19. An immunophenotypic comparison of metanephric metaplasia of Bowman capsular epithelium with metanephric adenoma, wilms tumor, and renal development: a case report and review of the literature.Metanephric metaplasia of the parietal epithelium of the bowman capsule is a rare pathologic finding of unknown pathogenesis that has occurred in patients with widespread malignant neoplasms of various types. We report this finding in a 25-year-old woman with partial expression of the Carney triad who died of a disseminated gastrointestinal stromal tumor, specifically a gastric stromal sarcoma. The metaplasia involved both kidneys diffusely. It originated in the parietal epithelium of the bowman capsule, extended into the proximal tubules, and focally surrounded the glomeruli in a semicircular manner Immunohistochemical analysis revealed that the cells of metanephric metaplasia expressed the wilms tumor gene product, bcl-2 protein, and CD57 and cytokeratin 7 and keratin AE1/AE3 focally, but not CD56. This immunophenotype parallels that of metanephric adenoma, wilms tumor, and nephrogenic rests and overlaps with antigen expression in certain periods of renal development.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
4/19. Passive seeding in metanephric adenoma: a review of pseudometastatic lesions in perinephric lymph nodes.Lymph node involvement derived from a discrete neoplastic process fundamentally implies tumor malignancy. However, rarely, inconsequential passive transport of benign neoplastic cells to the lymph node can occur and may cause confusion as to the nature of the neoplasm (ie, malignant vs benign). We describe a 10-cm right renal metanephric adenoma incidentally discovered in a 30-year-old woman during cesarean section for a triplet pregnancy. Subsequent nephrectomy following an equivocal needle biopsy diagnosis showed histologic features classic for metanephric adenoma, including the lack of cytologic atypia and mitoses. necrosis present in this lesion appeared to be secondary to tumor physical disruption. The tumor cells were positive for wilms tumor 1 (WT1) antigen, pankeratin, and CD57, focally positive for epithelial membrane antigen, and negative for cytokeratin 7, cytokeratin 34betaE12, and CD56. Electron microscopy confirmed the tumor's epithelial nature, and cytogenetics revealed a diploid 46XX karyotype. The tumor proliferation index with Ki-67 was only 3% to 5% and the proliferating cell nuclear antigen index was 0%. A single, concurrently resected hilar lymph node contained scattered subcapsular, sinusoidal, and focally intralymphovascular psammoma bodies along with occasional adherent epithelial cells. These cells were highlighted by pankeratin but were nonreactive to WT1 antigen, similar to the nonviable cells in the primary tumor. Clinical surveillance and follow-up showed no disease recurrence 4 years after nephrectomy. We postulate that the lymph node inclusions found in this case represent passive transport of neoplastic cells to the lymph node following manipulation of the renal mass. We conclude that this phenomenon is understudied and underrecognized and can easily be mistaken for metastasis.- - - - - - - - - - ranking = 4keywords = antigen (Clic here for more details about this article) |
5/19. adult Wilms' tumor. Intraoperative cytology and ancillary studies performed in a case as an adjunct to the histologic diagnosis.A case of blastema-predominant Wilms' tumor in a 64-year-old woman is reported. Intraoperative cytology of a renal mass was used to rule out malignant lymphoma and neuroendocrine carcinoma. light and electron microscopy, immunocytochemical staining and flow cytometry (FCM) were also performed. Immunoperoxidase studies of smears showed positive staining for vimentin and negative staining for cytokeratins and epithelial membrane antigen. FCM dna analysis of paraffin-embedded tissue showed no aneuploid peak. Frozen section interpretation of such tumors as seen in this case may be difficult, requiring distinction among several small-blue-cell neoplasms, including Wilms' tumor, neuroendocrine carcinoma and malignant lymphoma; intraoperative cytology can provide a valuable adjunct to frozen section diagnosis.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
6/19. A cell line from Wilms' tumour with deletion in short arm of chromosome II.A cell line (T3/73) from a Wilms' tumour has been established from a 9 month-old boy with aniridia. The tumour was removed in 1973. On histological examination a diagnosis of Wilms' tumour was made which showed undifferentiated areas, marked tubule formation and abundant striped muscle fibres. The tumour cells, which are fusiform, grew rapidly in culture without the addition of growth factors, and have undergone over 100 passages. Approximately 95% and 5% were positive for desmin and cytokeratin, respectively. The cell doubling time was 28 hr. Cytogenetic studies revealed a karyotype of 46,XY,del(11) (p12::p14). Although the cells stained very intensely with a monoclonal antibody that detects oncogene ras p 21 antigen, Southern blot analysis using c-Ha-ras as a probe failed to reveal an obvious deletion or amplification of either Ha-ras allele.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
7/19. Extrarenal Wilms' tumor: an analysis of four cases.During a review of Wilms' tumor, four located external to the kidney were identified. Patient age ranged from 7 months to 4 years; three were female. One neoplasm was located in the parametrial connective tissue to the left of the uterus; both kidneys were radiographically normal. Three neoplasms were located in the right retroperitoneum adherent to the surface of the ipsilateral kidney, but separated from the parenchyma by a thick fibrous capsule. Two were attached to the upper pole, while the third was attached to the midportion of the kidney. Radiologic studies showed displacement of all three kidneys, but intravenous pyelogram (IVP) revealed no calyceal distortion. All four neoplasms were favorable histology Wilms' tumor: one was monophasic epithelial type, one was monophasic blastemal type, and two had a mixture of stromal, epithelial, and blastemal tissue. No teratomatous elements were present. Immunoperoxidase staining for cytokeratin (AE-1, AE-3, CAM 5.2), vimentin, and epithelial membrane antigen (EMA) showed the strongest focal positive staining of tubular structures with CAM 5.2, and slight staining with EMA. Staining reaction to vimentin was variable, but negative in most areas. Three tumors extracted from paraffin were diploid by quantitative flow cytometric dna analysis; in one case, flow cytometry could not be performed. Clinical follow-up from 2 years to 6 years showed all children to be alive without evidence of disease. Based on the similarity to conventional renal Wilms' tumor, these findings support the hypothesis of displaced mesonephric/metanephric rests for the origin of extrarenal Wilms' tumor.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
8/19. Bilateral diffuse nephroblastomatosis, pancortical type. A case report with immunohistochemical investigations.A variation of Perlman's syndrome of the pancortical type is reported in a male neonate whose parents were cousins. The patient was the product of a 35-week pregnancy, the apgar score was 3, and the patient died of respiratory failure one hour and 12 minutes after delivery. autopsy revealed bilateral diffuse nephroblastomatosis, pancortical type, associated with malformations (usually facial), congenital anomalies of the heart, hepatosplenomegaly, pancreatic islet cell hyperplasia, bilateral cryptorchidism, and hyperflexibility of the left knee joint. Renal immunohistochemical investigations revealed positive bindings with peanut and soybean agglutinins and epithelial membrane antigen along the luminal surface of the epithelium in the moderately differentiated tubules, but not in blastoma or primitive epithelium.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
9/19. Characterization of glomeruli by immunohistochemistry and electron microscopy in a case of Wilms' tumor.A patient with an abdominal mass was found to have a Wilms' tumor. light microscopic examination showed that, in addition to blastema, stroma, and tubules, the tumor contained an unusually large number of glomeruli. Glomerular basement membranes stained positively by immunohistochemistry for laminin, collagen type iv, fibronectin, and Goodpasture antigen. Staining for Goodpasture antigen was seen only after acid-urea treatment, which was similar to findings in fetal and infant glomeruli. Glomerular cells stained positively for actin, myosin, and desmin, but there was no staining for factor viii or ulex europaeus agglutinin I, indicating an absence of endothelial cells. These findings were supported by electron microscopy, which showed basement membrane material, visceral epithelial cells, and mesenchymal cells (presumably primitive mesangial cells) in glomeruli, but no patent capillaries or capillary endothelium. Hence, the glomeruli in this case of Wilms' tumor were immature and also showed aberrant glomerulogenesis.- - - - - - - - - - ranking = 2keywords = antigen (Clic here for more details about this article) |
10/19. Blastemal cells of nephroblastomatosis complex share an onco-developmental antigen with embryonic kidney and Wilms' tumor. An immunohistochemical study on polysialic acid distribution.Previous investigations on polysialic acid of the neural cell adhesion molecule NCAM in human kidney have demonstrated its presence during nephrogenesis in embryonic kidney, absence in normal adult kidney, and reexpression in Wilms' tumor. These data showed that polysialic acid of NCAM is an onco-developmental antigen in human kidney and provided more direct evidence for the metanephric origin of Wilms' tumor. In the present study, five cases of Wilms' tumor associated with nephroblastomatosis complexes were immunohistochemically investigated with a monoclonal antibody for the presence of polysialic acid. Regardless of the type of nephroblastomatosis complex, ie, renal nodular blastema, simple tubular metanephric hamartoma, sclerosing metanephric hamartoma with adenoma, or incipient Wilms' tumor, immunoreactivity for polysialic acid was found in the blastemal cells, but was undetectable in all other structural elements. Because only blastemal cells exhibited a characteristic feature of embryonal differentiating metanephric derivatives, it appears that Wilms' tumor has its origin not exclusively in nodular renal blastema but rather in blastemal cells present in the various forms of nephroblastomatosis complex. The presence of polysialic acid of NCAM in blastemal cells in such lesions indicates that further events in addition to the expression of the embryonic form of this cell adhesion molecule may be involved in the pathogenesis of Wilms' tumor.- - - - - - - - - - ranking = 5keywords = antigen (Clic here for more details about this article) |
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