Malignant mixed epithelial and stromal tumor of the kidney.
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Biomedical subjects
Publications and source records attributed to M Michal.
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AIMS: We report the clinicopathological and immunohistochemical characteristics of 12 cases of a recently recognized entity, oncocytic papillary thyroid carcinoma (PC) with lymphoid stroma (Warthin-like tumour). METHODS AND RESULTS: The cases were retrieved from the surgical pathology files of our departments. There were 11 female patients and one male patient; they ranged in age from 45 to 85 years (mean 64.2 years). The immunohistochemical profile demonstrated positivity of tumour cells for cytokeratins, thyroglobulin, Leu-M1 and anti-mitochondrial antigen. S100 protein-positive stromal dendritic/Langerhans cells were uniformly present. Polymerase chain reaction, in situ hybridization, and immunohistochemistry for Epstein-Barr virus (EBV) detection revealed no significant positive signal. MIB-1 labelling index was low, compatible with that of 'classical' PC. CONCLUSIONS: Warthin-like tumour is a rare variant of PC, occurring predominantly in elderly women. Its histological features are distinct and well recognizable, differentiating this tumour from a more aggressive tall-cell variant of PC. The apparent indolent behaviour seems to be consistent with the presence of dendritic/Langerhans cells and with low proliferative activity. A possible role of EBV in pathogenesis of this lesion was not proven. Further studies are necessary to determine the prognosis and metastatic potential of this neoplasm.
Two cases of nuchal fibrocartilaginous pseudotumor are reported. The lesions occurred in a 50-year-old woman and a 41-year-old man. From the clinical point of view, the absence of history of trauma in one case represents an unusual observation. Histologically, both lesions were similar to the 10 cases which have been previously described. They consisted of poorly defined, moderately cellular fibrocartilage nodules, and they lacked nuclear atypia and mitotic activity. Immunohistochemically, the lesions showed diffuse expression of vimentin and CD34. Mild expression of S-100 was limited to some chondroid cells. Desmin, alpha-smooth muscle actin, and CD99 (MIC2 gene product) were not expressed. Ultrastructurally, cells with features of fibroblasts and chondroblasts without any signs of myofibroblastic or myochondroblastic differentiation were found.
Purely benign mesenchymal spindle cell neoplasms of the breast are currently labeled under various terms in the literature (benign spindle cell tumor, fibroma, spindle cell lipoma, myofibroblastoma, solitary fibrous tumor, myogenic stromal tumor). The lack of strict diagnostic criteria to clearly indicate such mesenchymal neoplasms is the main reason which generated the risk of terming the same lesion under different names or, conversely, of collecting different types under the same term. Although such neoplasms exhibit morphological and immunophenotypical heterogeneity, they actually represent variations of the same tumor entity, likely arising from the uncommitted vimentin+/CD34+ fibroblasts of the mammary stroma, capable of multidirectional mesenchymal differentiation. To cover the entire spectrum of such lesions, the term "benign spindle cell tumors (BSCTs) of the mammary stroma" is advocated. BSCTs can be subtyped into four main groups by light microscopy (LM) and immunocytochemistry (ICC): fibroblastic, myofibroblastic, fibrohistiocytic, and mixed forms. A simple and practical approach to a nosologically correct diagnosis and a list of differential diagnoses are presented. The awareness of the diversity of morphological and immunophenotypical features of BSCTs of the mammary stroma, including uncommon variants, is helpful to avoid confusion with other monomorphic bland-looking benign and malignant spindle cell tumors and tumor-like lesions of the breast.
Among 99 cases of neurofibroma (NF), eight tumors (8%) contained epithelial membrane antigen (EMA)-positive perineurial cells inside the lesions. These cells were numerous and represented a significant part of the tumor cell population. In case 7, EMA-positive cells represented approximately half of the tumor. These patients' ages ranged from 23 to 73 years (average 51 years). Six patients were females and two were males. Neurofibromatosis type 1 was present in one case. The histological types of neurofibromas with EMA-positive cells were as follows: cutaneous, well-circumscribed, localized type in four cases; cutaneous diffuse type in one case; subcutaneous, well-circumscribed type in two cases; and subcutaneous plexiform type in one case. Perineurial cell differentiation was suspected by examining routinely stained sections in four cases; it was unsuspected in four cases. The perineurial cells were arranged in a pattern similar to that of "pure" perineurioma. They possessed thin bipolar processes and were arranged in laminar fascicles and whorls. In cellular areas, the cytoplasm was more eosinophilic and cell borders were poorly visible. In contrast, when the stroma was myxoid, it accentuated the shape of individual cells. As these morphological features of perineurial cell differentiation in NF are not entirely specific, EMA staining is recommended to prove the perineurial cell differentiation in neurofibromas. An additional immunohistochemical result of this study is the presence of numerous CD34-positive cells in all neurofibromas, which is similar to previous studies.
The authors present 18 cases of a hitherto unrecognized variant of cutaneous neurofibroma. The tumors presented in adults (10 occurred in men and eight occurred in women) as a solitary, well-circumscribed, superficial lesion located in the dermis measuring 3 to 17 mm (mean size, 6.2 mm). The tumors formed oval-shaped masses that ran perpendicular to the epidermis. In the deep part of the tumor there was multinodular arrangement with two types of cells: Type I cells were small, dark, lymphocyte-like cells with a slightly irregular nucleus and inconspicuous cytoplasm. Type II cells were larger, with pale-staining vesicular nuclei, with frequent invaginations and intranuclear inclusions, and had copious clear eosinophilic cytoplasm that formed a stellate growth pattern, which was poorly visible on hematoxylin and eosin staining. Type I cells were grouped concentrically around type II cells and formed pseudorosettes. Most of the type I and type II cells were S-100 protein and CD57 positive, and various proportions of both cell types were CD56 and PGP9.5 positive. All cells were chromogranin A, synaptophysin, glial fibrillary acidic protein, cytokeratins, CD1a, CD21, CD31, alpha-smooth muscle actin, muscle-specific actin, desmin, and HMB-45 negative. CD34 stained intralesional fibroblasts. Antibody to epithelial membrane antigen stained only the perineurium around the tumor masses, suggesting that the tumors arose inside the nerve sheath. No signs of neurosecretory granules were present at ultrastructural level. None of the lesions recurred and none metastasized over a mean follow-up of 8.1 years.
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Here we report 3 cases of renal oncocytoma with a dominating small cell component arising in adult women. These 3 cases of small cell variant of renal oncocytoma were found among 134 cases of oncocytomas of the kidney in the routine and consultation files of the authors. Two of 3 cases were initially thought to be a malignant tumor by the referring pathologists. In all 3 cases minor areas of the tumors, which were identical to the classical renal oncocytomas were found. The small cell areas were arranged in a characteristic organoid pattern different from all the known types of the renal benign and malignant tumors. We summarize all morphologic, immunohistochemical, and ultrastructural features of this unusual oncocytoma variant with regard to its differential diagnosis. Int J Surg Pathol 9(3):215-222, 2001
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From the collection of 2500 cases of renal epithelial tumors in our files, 102 renal oncocytomas were analyzed for size, multifocality and a morphologic spectrum of the growth pattern. The size of the tumors ranged from 1.5 to 13 cm in diameter, with a mean of 6.3 cm. Three cases were multifocal, four cases were combined with another primary renal tumor (1x angiomyolipoma, 1x conventional renal carcinoma, 2x papillary renal cell carcinoma). A central fibrosis or a scar was noted in 13 cases, and there was a gross area of hemorrhage in 11 cases. In 4 cases extensive necroses were recognized. Histologically, an alveolar pattern was noted in 70 cases. A tubular pattern was revealed in 31 cases and an unusual tubopapillar ("glomeruloid") pattern was noted in one case. Foci of atypical nuclei were identified in 58 cases. In 4 oncocytomas broad areas of clearance of the oncocytes were found. Psammoma bodies were recognized in 9 tumors and foci of ossification were present in 4 cases. Intracellular and extracellular hyaline globules were noted in two cases. Renal oncocytoma has a variable morphologic spectrum, and its diagnosis should be based on an analysis of structural and cytologic features. Differential diagnosis of renal oncocytomas with various tumors of the kidney which contain granular cytoplasm is discussed. These tumors with granular cytoplasm include conventional renal cell carcinomas, chromophobe cell carcinomas, and rare examples of papillary renal carcinomas.
In physiological instances, the prostatic acini may be intermingled with striated muscle fibers in the apex and in the anterolateral subcapsular areas of the prostate. We report an unusual lesion composed of benign prostatic glands, which were scattered between skeletal muscle fibers beneath the bladder submucosa. A 55-year-old man underwent four transurethral resections and radiation therapy for a urothelial carcinoma of the urinary bladder. Subsequently a cystectomy was performed. In the resection specimen, the prostate specific antigen-positive glands were found among the skeletal muscle bundles close to the bladder submucosa. They were seen as small groups of haphazardly scattered or isolated glands mimicking an infiltrative pattern of a prostatic adenocarcinoma. Prominent nucleoli in some glands further contributed to the worrisome appearance of the lesion. However, the high molecular weight cytokeratin 34 beta E12 exhibited basal cell layers of the glands, and the subsequent course of disease confirmed the benign nature of the lesion. The juxtaposition of the prostatic acini with the skeletal muscle out of the apex and the anterolateral subcapsular areas of the prostate should be included in the differential diagnosis of prostatic carcinoma in urinary bladder and prostate biopsies.
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OBJECTIVES: This multi-methodical single case study examines how relationship, resistance and insight, the important therapeutic factors, are conveyed in a therapeutic process. METHODS: For depicting interaction the textual parameters - direct speech, acknowledgement tokens, activity of speech and personal pronouns - of Formal Psycholinguistic Text Analysis (Overbeck et al., 1996) are applied. The activity of the unconscious theme is measured by the Interferenzindex (Argelander, 1984). The link of emotional experiences with words is depicted by the Computerized Referential Activity method (Mergenthaler and Bucci, 1999). The attainment of emotional insight in the Model of the Therapeutic Cycle is perceived via the Emotion-/Abstraction-Patterns (Mergenthaler, 1997). RESULTS: Three phases are discriminated accordingly: Resistance, characterised by defensive intellectualization, symbolic representation on the basis of the secure relationship and emotional insight and detachment. CONCLUSIONS: The validity of the results in this single case study is guaranteed by the multi-methodical strategy.
Sclerosing epithelioid fibrosarcoma (SEF) was first described in 1995 and since then 39 cases have been reported. Here we describe 6 cases of SEF (3 in women and 3 in men). The patients aged from 22 to 79 years. The tumours were located in soft tissues of the extremities (in 3 cases in the lower, in 2 instances in the upper extremity) and of the trunk (in 1 case). The lesions were partially nodular, of gray-white colour, and hard in consistency. Histologically, they were composed of epithelioid round to ovoid small cells with a sparse cytoplasm and a very low mitotic activity. The tumour cells formed cords and alveoli or were scattered individually within a dense hyalinized collagenous stroma. The neoplasms also contained foci of conventional fibrosarcoma, necrosis, calcification, and metaplastic bone. On immunohistochemistry, the neoplastic cells were positive for vimentin. Two cases were immunoreactive for epithelial membrane antigen and one tumour also for cytokeratins. The proliferative activity, assessed by MIB 1 antibody (Ki-67), was detected in 1-6% of neoplastic cells in primary tumours. Follow-up information was available in 5 patients. In two cases, there were local recurrences and distant metastases (in the lungs, upper extremity, and mediastinum). One of these patients died of SEF. The differential diagnosis of this relatively low-grade fibrosarcoma is broad and includes, along with a variety of benign and malignant soft tissue lesions, infiltrating carcinoma, and, to a lesser extent, sclerosing lymphoma.
We report two cases of prolapse of the fallopian tube associated with an exuberant angiomyofibroblastic stroma response, which occurred after hysterectomy and which is a hitherto unreported feature of this lesion. The tumors were composed of richly vascularized stroma arranged in a retiform pattern and mildly atypical glandular inclusions, which had the morphology of tubal epithelium. The stroma of the lesion was composed of either thin bipolar cells with tapered nuclei and stellate-shaped cells with minimal amount of cytoplasm or small epithelioid-looking cells with eosinophilic cytoplasm. The tubal glandular inclusions displayed mildly atypical nuclear features. If the tubal glandular component was overlooked, these tumors might be erroneously diagnosed as mesenchymal lesions of the vagina, such as vaginal fibroepithelial polyp, angiomyofibroblastoma, aggressive angiomyxoma, or superficial myofibroblastoma.
We describe a 45-year-old man who had a 2-year history of a slowly enlarging tumor in the left parotid gland. Histologically, the tumor was a mucinous cystadenoma with focal apocrine differentiation, which revealed a widespread invasive micropapillary adenocarcinoma component. A rim of lymphoid tissue surrounded the margins of the micropapillary carcinoma. The invasive micropapillary adenocarcinoma component was morphologically identical with the invasive micropapillary carcinoma of the mammary gland. The tumor is different from so-far recognized salivary gland tumor entities.
We report on two cases of myofibroblastoma (MFB) of the breast comprised predominantly of a mature fatty component, representing approximately three quarters of the entire tumour area. Both tumours consisted of a well-circumscribed lipomatous tumour mass containing dispersed nodular or irregularly shaped spindled cellular areas. The fatty component was represented exclusively by mature adipocytes, uniform in size and shape, lacking nuclear pleomorphism. The cellular areas contained spindly to oval cells with morphological and immunophenotypical features typical of MFB. The two components were so intimately admixed that a finger-like infiltrating growth pattern was apparent. The cases reported here as "lipomatous MFB" aim to clarify further the morphological spectrum of MFB of the breast. Lipomatous MFB may potentially mimic other benign or aggressive tumour-like lesions or even bland-looking malignant spindle cell tumours such as fibromatosis, nodular fasciitis, spindle cell lipoma, spindle cell liposarcoma, spindle cell variant of metaplastic carcinoma, spindle cell malignant myoepithelioma, and low-grade fibrosarcoma/malignant fibrous histiocytoma. The histogenesis of the present bimorphic mesenchymal tumours could be explained as the result of a dual, myofibroblastic and lipomatous, differentiation from a common pluripotential mesenchymal precursor cell, probably represented by the vimentin+/CD34+ fibroblast of the mammary stroma.
We describe a unique benign mesenchymal tumor in paraspinal location in a 13-year-old patient with Gardner's syndrome. The Gardner's syndrome in this patient consisted of multiple (more than 100) polyps throughout the entire colon with most in the cecum and rectum, three osteomas in the frontal area of the skull and one in the third right rib, and multiple superficial skin tumors. One of these cutaneous tumors was excised and histologically diagnosed as an epidermal cyst. Both father and uncle of this patient suffered from Gardner's syndrome as well. Microscopically the mesenchymal tumor was histologically different from nuchal type fibroma and fibromatosis. It consisted of a diffusely-growing fibrous mass composed of dense collagenous fibers and relatively numerous, bland-looking, spindle-shaped cells. The collagen fibers had haphazard spacing with no lobular arrangement. The collagen fibers were of a very coarse quality. No entrapment of adipose tissue, skeletal muscle or peripheral nerves was seen in the lesion. Immunohistochemically the tumor was vimentin positive and smooth muscle actin, muscle-specific actin, S-100 protein, cytokeratin and desmin negative.