1/11. adult mesoblastic nephroma.We report a case of asymptomatic mesoblastic nephroma in a 54-year-old woman. The tumor showed immunohistochemical reactions similar to developing nephrons. Electron microscopy showed immature tubules with numerous intracytoplasmic intermediate filaments. Recent studies support the concept of pathogenesis of the mesoblastic nephroma originating from collecting ducts. However, this case exhibited a complex pattern of antigenic expression not restricted to the collecting ducts, but including the glycoprotein CD24 and the neural cell adhesion molecule (NCAM). The following differential diagnoses will be discussed: benign mixed epithelial and stromal tumor, metanephric adenoma, and nephrogenic adenofibroma.- - - - - - - - - - ranking = 1keywords = stromal (Clic here for more details about this article) |
2/11. Glandular patterns in a thyroid carcinoma with insular and anaplastic features: a case with possible implications for the classification of thyroid carcinomas.We describe the case of a 33-year-old woman with a thyroid carcinoma showing poorly differentiated (insular), anaplastic, and glandular features, the latter with extensive clear cell changes. Grossly, the well-circumscribed tumor nodule measured 3.6 cm in maximum dimension and was confined to the thyroid. Microscopically, the majority of the tumor was composed of well-defined "insular" nests showing microfollicular formation, high mitotic activity, and areas of necrosis. Other regions, as well as the intervening stroma of the insular nests, were characterized by highly atypical and pleomorphic stromal cells, extensive necrosis, and malignant cartilaginous nodules. Approximately 30% of the tumor was composed of diffuse glandular formations, each of which were lined by elongated, simple columnar cells with basally situated, mildly pleomorphic nuclei, clear supranuclear, periodic acid-Schiff (and diastase sensitive) cytoplasm, empty lumens, and no myoepithelia or basement membranes. Immunohistochemically, the glandular elements displayed diffuse and strong positivity for thyroid transcription factor-1, bcl-2, and CAM 5.2, sparse positivity for thyroglobulin and Ki67, and diffuse but weak positivity for p53. calcitonin was negative throughout the tumor. Karyotypic analysis of a primary culture showed a complex hypertriploid karyotype including structural abnormalities of chromosomes X, 1, 4, 6, 9, 13, and 14 in the majority of cells examined. This composite of histologic findings, especially the glandular patterns, is unusual and their prognostic significance is unclear. The patient is alive with no evidence of tumor recurrence or metastasis at 5 months follow-up. overall, the morphologic and immunohistochemical properties of the glandular component suggests that they are less differentiated than well-differentiated carcinomas and are probably more differentiated than the insular component. This case supports the theory that the various primary carcinomas of the thyroid may represent points along a spectrum rather than distinct entities.- - - - - - - - - - ranking = 1keywords = stromal (Clic here for more details about this article) |
3/11. Peritoneal cytology of uncommon ovarian tumors.Peritoneal cytology has been well established as a diagnostic and staging tool in the management of the common epithelial tumors of ovary. Germ cell, mesenchymal, and sex-cord stromal tumors are much less frequently encountered in peritoneal specimens, often with cytologic features that may pose problems in differential diagnosis. This report presents the cytomorphology of the ascitic fluid in cases of endodermal sinus tumor, dysgerminoma, and Sertoli-Leydig-cell tumor, and peritoneal washings in a case of ovarian malignant mixed mullerian tumor. The cytologic features of Sertoli-Leydig-cell tumors have not been well described. Careful correlation of peritoneal cytologic findings, cell-block preparations, and immunocytochemistry with the cytohistologic features of these tumors is crucial for correct tumor classification.- - - - - - - - - - ranking = 1keywords = stromal (Clic here for more details about this article) |
4/11. Benign mixed epithelial and stromal tumor of the kidney (MEST) with cytogenetic alteration.Benign mixed epithelial and stromal tumor of the kidney (MEST) is a new, rare entity. These tumors are composed of two components: a stromal and an epithelial one. Clinical outcome is usually good, no specific cytogenetic alterations have been described up to now. We describe for the first time a case with translocation t (1; 19).- - - - - - - - - - ranking = 6keywords = stromal (Clic here for more details about this article) |
5/11. Incidental stromal-predominant mixed epithelial-stromal tumors of the kidney: a mimic of intraparenchymal renal leiomyoma.CONTEXT: Mixed epithelial-stromal tumor of the kidney is a recently recognized benign renal tumor that usually occurs in adult women and typically forms a sizable lesion with solid and cystic areas. The recognized morphologic spectrum of this recently described entity is evolving. OBJECTIVE: To review the clinicopathologic features of 3 small mixed epithelial-stromal tumors of the kidney that were incidental findings in kidneys removed for other reasons. DESIGN: The clinical presentation and morphologic findings of the 3 cases were reviewed. A panel of immunohistochemical stains was performed. SETTING: Academic medical center. RESULTS: All 3 lesions contained predominantly fascicles of smooth muscle mimicking leiomyoma, but they also had cellular subpopulations of smaller, mullerian-appearing stromal cells. Tubules present within the lesion were most abundant at the periphery, suggesting that they might be entrapped. Although only the spindled smooth muscle cells were immunoreactive for muscle markers desmin and actin, both the spindled smooth muscle cells and the cellular mullerian-appearing stromal cells demonstrated diffuse nuclear labeling for estrogen and progesterone receptors. CONCLUSIONS: Mixed epithelial-stromal tumor of the kidney may present as an incidental stromal-predominant lesion within the kidney. Such lesions are easily confused with leiomyomas or stromal-predominant angiomyolipomas.- - - - - - - - - - ranking = 15keywords = stromal (Clic here for more details about this article) |
6/11. Mixed epithelial and stromal tumor of the kidney in a 12-year-old girl.Mixed epithelial and stromal tumor of the kidney (MESTK) is a rare kidney neoplasm that almost exclusively occurs in perimenopausal women, and long-term estrogen replacement is relevant to its pathogenesis. Herein is described an atypical case of MESTK uncovered in a 12-year-old premenarcheal girl without a history of prior estrogen use. On surgical specimen it was found that the well-circumscribed tumor measuring 14 cm arose from the lower pole of the right kidney, showing solid and fibrous-cystic areas. Microscopically, it was composed both of epithelial structures similar to renal tubules and stroma comprising non-specific spindle cells. Some intratumoral tubules showed affinities to distal-nephron-specific lectins, and those immunoreactive for proximal-tubule-specific CD15 were also present. In addition, primitive ductal structures were reactive both for CD15 and lectins, but immature epithelial elements typical of nephroblastoma were absent. Spindle cells were positive for actin, desmin and vimentin, and expressed progesterone and estrogen receptors. The tumor was comparable with MESTK, although some epithelia were associated with the immunophenotype of proximal tubules. The patient was free of disease postoperatively for 40 months. In the present case, remnants of the primitive periductal mesenchyme might be promoted to neoplastic cells by a sex-steroid surge during puberty.- - - - - - - - - - ranking = 5keywords = stromal (Clic here for more details about this article) |
7/11. Benign mixed epithelial and stromal tumor of the kidney: imaging findings.Three cases of mixed epithelial and stromal tumor of the kidney with their imaging findings are described; these cases have not been reported previously in the radiology literature. This benign tumor contains epithelial and spindle cell stromal components and arises exclusively in adult women. It is characterized morphologically by a solid and cystic nature with delayed enhancement.- - - - - - - - - - ranking = 6keywords = stromal (Clic here for more details about this article) |
8/11. Mixed epithelial and stromal tumor of the kidney.A 42-year-old female presented with intermittent left flank pain for 2 years. She developed gross hematuria 1 month prior to seeking help. Intravenous pyelography showed filling defects within the lower portion of the left collecting system and renal pelvis causing hydronephrosis. Abdominal computed tomography revealed a huge cystic heterogenic tumor about 20 cm in largest diameter occupying the entire left kidney. A left radical nephrectomy was performed without complications. The pathology report confirmed the diagnosis of mixed epithelial and stromal tumor of the kidney. From pathologic survey, the spindle cells of this tumor were positive for muscle markers and expressed estrogen and/or progesterone receptors. We suggest that a mixed epithelial and stromal tumor of the kidney should be considered in all cystic renal tumors presenting in perimenopausal women.- - - - - - - - - - ranking = 6keywords = stromal (Clic here for more details about this article) |
9/11. Epithelial stromal tumor of the seminal vesicle.Primary tumors of the seminal vesicles are rare neoplasms; there have been only 69 accepted cases. The histologic features are usually adenocarcinoma; however, there are rarely reported epithelial stromal tumors of the seminal vesicles. We report a case of a 70-year-old man with an epithelial stromal tumor of the seminal vesicle who presented without symptoms of bladder outlet obstruction. The patient underwent radical cystoprostatectomy. No signs of tumor recurrence were noted within 14 months of surgery. To our knowledge, 13 cases of epithelial stromal tumors of the seminal vesicle have been previously reported.- - - - - - - - - - ranking = 7keywords = stromal (Clic here for more details about this article) |
10/11. Synovial sarcoma with squamous differentiation of its mesenchymal glandular elements. A case report with light-microscopic, ultramicroscopic, and immunologic correlation.A 25-year-old male patient with a biphasic synovial sarcoma of his right flank is reported. The tumor was not only richly glandular but also showed a rare finding in association with a sarcoma, namely, squamous differentiation. light microscopy and electron microscopy demonstrated the classical features of a biphasic synovial sarcoma except for foci of squamous change. Antibody stain directed against keratin demonstrated this substance in both the glandular and squamous cells but not in the stromal elements. Therefore, the finding of squamous differentiation in association with a malignant, deep soft-tissue tumor must include in the differential diagnosis not only carcinomas but rare sarcomas as well, including the biphasic synovial sarcoma and the glandulosquamous variant of malignant schwanomma.- - - - - - - - - - ranking = 1keywords = stromal (Clic here for more details about this article) |
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