1/116. US and CT findings of multicentric leiomyosarcomatosis.This article presents a case of leiomyosarcomatosis with widespread lesions involving the soft tissues and the most unlikely organs such as thyroid and salivary glands, pancreas, ligamentum teres, bladder wall, and bones without lymph node or distant metastasis. The CT and US findings of this rare phenomenon are discussed with regard to the literature.- - - - - - - - - - ranking = 1keywords = ligament (Clic here for more details about this article) |
2/116. Fine-needle aspiration cytology of hemangiopericytoma: A report of five cases.BACKGROUND: hemangiopericytoma (HPC) is a relatively rare neoplasm, accounting for approximately 2.5% of all soft tissue tumors. Its histopathology has been well documented but to the authors' knowledge reports regarding its fine-needle aspiration (FNA) cytology rarely are encountered. In the current study the authors report the cytologic findings in FNA specimens from nine confirmed cases of HPC and attempt to correlate the cytologic features with the biologic outcomes. methods: FNA was performed with or without radiologic guidance. Corresponding sections of tissue were reviewed in conjunction with the cytologic preparations. RESULTS: Nine FNAs were performed in 5 patients (3 men and 2 women) with an age range of 38-77 years (mean, 56 years). Two lesions were primary soft tissue lesions arising in the lower extremities; seven were recurrent or metastatic lesions from bone (one lesion), kidney (one lesion), pelvic fossa (one lesion), lower extremities (two lesions), trunk (one lesion), and breast (one lesion). All aspirates were cellular and were comprised of single and tightly packed clusters of oval to spindle-shaped cells aggregated around branched capillaries. basement membrane material was observed in 6 cases (67%). The nuclei were uniform and oval, with finely granular chromatin and inconspicuous nucleoli in all cases except one. No mitotic figures or areas of necrosis were identified. A correct diagnosis of HPC was made on one primary lesion and all recurrent or metastatic lesions. CONCLUSIONS: HPCs show a spindle cell pattern in cytologic preparations and must be distinguished from more common spindle cell lesions. The presence of branched capillaries and abundant basement membrane material supports a diagnosis of HPC. immunohistochemistry and electron microscopy performed on FNA samples may be helpful in the differential diagnosis. FNA is a useful and accurate tool with which to confirm recurrent or metastatic HPC; however, prediction of the biologic behavior of HPC based on cytologic features is not feasible. Cancer (Cancer Cytopathol) copyright 1999 american cancer society.- - - - - - - - - - ranking = 0.17243029593262keywords = membrane (Clic here for more details about this article) |
3/116. Low-grade malignant perineurioma of the paravertebral column, transforming into a high-grade malignancy.A demarcated 6 x 5 cm right paravertebral tumor at the level of T6 in a 39-year-old male was removed surgically. Histologically, the tumor consisted of monomorphous benign-looking, low-cellular spindle cells embedded in desmoplastic stroma. Ten years later, the tumor recurred locally with metastasis to systemic organs, including the occipital skin. Malignancy was histologically evident by the increased cellularity, cellular atypia and mitotic activity. The patient died of respiratory failure at the age of 49. Retrospectively reviewed, the primary lesion was low-grade fibrosarcoma-like spindle cell tumor, with secondary transformation into a highly malignant form. The differential diagnoses included sclerosing epithelioid fibrosarcoma, low-grade fibromyxoid sarcoma and malignant peripheral nerve sheath tumor. Immunohistochemically, the spindle cells in the primary and recurrent tumors consistently expressed epithelial membrane antigen, vimentin, type 4 collagen and laminin. The tumor cells in the present case showed a differentiation toward perineurial cells, which are normally positive for these immunohistochemical markers. Hence, the appropriate diagnostic term should be 'malignant perineurioma', a subtype of malignant peripheral nerve sheath tumor.- - - - - - - - - - ranking = 0.086215147966308keywords = membrane (Clic here for more details about this article) |
4/116. Primary desmoplastic small cell tumor of soft tissues and bone of the hand.Desmoplastic small cell tumor (DSCT) is a high-grade malignant neoplasm that shows polyphenotypic differentiation. Its almost exclusive involvement of serosal surfaces (particularly peritoneum) has led to the consideration of a putative "mesothelioblast" as the cell of origin. Although an extraserosal case involving the brain (presumably arising from the dura) has been reported, to date no case primary in the bone or soft tissues has been documented. The authors describe a 34-year-old man who presented with a 3-year history of pain in the right hand and a recently noted mass in the hypothenar area. Open biopsy followed by wide en bloc excision in combination with index ray resection was performed. Subsequently, the patient underwent ipsilateral axillary lymph node dissection. Extensive radiologic workup at the time of presentation and 12 months later revealed no tumor in the chest or abdomen. The patient was treated with an HD-CAV chemotherapy regimen (cyclophosphamide, doxorubicin, vincristine, ifosfamide, etoposide) and was free of tumor until 18 months later, at which time he developed multiple metastases in the lungs. Currently, he is alive with tumor and in poor condition. The histologic sections of the mass displayed the characteristic features of DSCT involving bone and soft tissue. Immunohistochemical stains showed positivity of the tumor cells for muscle marker (desmin), neuroendocrine markers (chromogranin, synaptophysin), and epithelial markers (keratins CAM5.2, AE1:AE3, epithelial membrane antigen). Chimeric transcripts were detected by reverse transcriptase-polymerase chain reaction, indicating the presence of EWS-WT1 gene fusion, which is characteristically associated with DSCT. sequence analysis showed in-frame fusion of EWS exon 9 to WT1 exon 8--a variant not documented in any other case. This is a unique example of DSCT primary in bone and soft tissues, which raises interesting questions about the histogenesis of this tumor type and its relationship to other small round cell tumors. Although the "mesothelioblast" hypothesis as the origin of DSCTs is attractive, it does not account for the tumors that are located in the brain or, as in this patient, in the soft tissues and bone. In addition, this patient demonstrates a rare variant of EWS-WT1 gene fusion not described in DSCT involving serosal surfaces.- - - - - - - - - - ranking = 0.086215147966308keywords = membrane (Clic here for more details about this article) |
5/116. Epithelioid sarcoma: report of two cases diagnosed by fine-needle aspiration biopsy with immunocytochemical correlation.Epithelioid sarcoma (ES) is an aggressive soft-tissue malignant tumor generally arising in the distal extremities of young adults. The microscopic diagnosis of ES is often difficult because of its rarity and its possible confusion with other malignant tumors or even with benign granulomatous processes. Two cases of ES and a recurrence of one of these tumors, diagnosed by fine-needle aspiration biopsy (FNAB), are reported. Cytologic smears were quite similar in both cases including the relapse, showing single or loosely arranged groups of medium to large atypical cells. Single cells had well-defined eosinophilic cytoplasms and one or more atypical, eccentrically located nuclei, resulting in a plasmacytoid appearance. Nuclei had fine granular chromatin and one or two large nucleoli. The cells sometimes palisaded along the edges of necrotic material. The immunocytochemical stains showed diffuse cytoplasmic positivity for cytokeratins (CAM 5.2) and both cytoplasmic and cell membrane positivity for vimentin, while S-100 protein and HMB 45 immunostaining were negative, thus supporting the cytological diagnosis of ES, which was subsequently proven on the surgical samples. Diagn. Cytopathol. 1999;21:405-408.- - - - - - - - - - ranking = 0.086215147966308keywords = membrane (Clic here for more details about this article) |
6/116. Extraneural retiform perineuriomas. A report of four cases.We present here four cases of extraneural perineurioma (EP), which occurred in 31, 32, 42 and 43 year old women in the left hand, right arm (2 cases) and right axillary regions, respectively. All tumors were well circumscribed, with a thin capsule. They were 2, 2, 1.5 and 1.5 cm in the largest diameter. Microscopically all tumors had a distinctive appearance composed of interconnected cords of cells which ran in a parallel fashion or formed a characteristically looking cellular lattice. These cords were composed of cells with tapered to stellate shaped nuclei having one or two inconspicuous nucleoli. The space between the cells of the lattice was edematous and empty looking, or it was composed of myxoid matrix, or it was filled with characteristically looking globular deposits of collagen extracellular matrix. These globular deposits of collagen extracellular matrix often indented the nuclei, giving them a stellar appearance. Immunohistochemically all tumors reacted positively with antibodies to epithelial membrane antigen. antibodies to smooth muscle actin, muscle-specific actin, S-100 protein, cytokeratin AE1/AE3, cytokeratin CAM 5.2, and HMB-45 gave uniformly negative immunohistochemical results.- - - - - - - - - - ranking = 0.086215147966308keywords = membrane (Clic here for more details about this article) |
7/116. Extraskeletal osteosarcoma of the scalp.A rare case of extraskeletal osteosarcoma of the scalp in a 56-year-old woman is described. At presentation she was found to have an 8-cm diameter, tender, firm, exophytic scalp tumor. MRI scan confirmed absence of underlying skeletal origin and showed extension along the subcutaneous plane. The tumor was excised and the patient received post-operative chemotherapy. Histologically, the tumor showed classical features of an osteogenic osteosarcoma with focal fibroblastic areas. In addition, there were rhabdoid cells present, which showed paranuclear cytoplasmic immunoreactivity for epithelial membrane antigen. The patient developed metastatic disease 6 months after surgical excision.- - - - - - - - - - ranking = 0.086215147966308keywords = membrane (Clic here for more details about this article) |
8/116. Functional nerve growth factor receptor in von Recklinghausen neurofibromatosis: an immunocytochemical and short-term culture study.Immunocytochemistry reveals 75 kDa low affinity type nerve growth factor receptor (NGFR) on the cell membrane of human neurofibroma cells of von Recklinghausen disease in vivo and in vitro. NGF-immunoreactivity is detected in the primary and cultured tumor cells. Growth augmentation of cultured neurofibroma cells by exogenous NGF is also confirmed. phosphotyrosine-immunoreactivity is demonstrated by immunocytochemistry in the in vivo and in vitro neurofibroma cells suggesting possible phosphorylation of tyrosine residue in the NGFR or a cellular protein downstream of signal transduction through the ligand receptor system. These results indicate human neurofibroma cells possess functional NGFR and the growth is potentiated through the NGF-NGFR system in the paracrine and/or autocrine fashion.- - - - - - - - - - ranking = 0.086215147966308keywords = membrane (Clic here for more details about this article) |
9/116. Sclerosing epithelioid fibrosarcoma: a cytogenetic, immunohistochemical, and ultrastructural study of an unusual histological variant.A case of sclerosing epithelioid fibrosarcoma was studied. The tumor cells expressed vimentin, focally epithelial membrane antigen and CD34, contained cisternae of rough endoplasmic reticulum, large golgi apparatus, many pinocytotic vesicles, and were devoid of basal lamina. Their composite karyotype was 45,Y,t(X;6)(q13;q15), t(6;13)(p11.2;q13),-22 inverted question mark2/46,Y,t(X;6)(q13;q15),add(13)(p12), add(22)(q13) inverted question mark3/44 approximately 46,der(X)t(X;6)(q13;q21),-Y, t(13;14)(q10;q10),-22,add(22)(q13) inverted question mark7/46,XY inverted question mark8.- - - - - - - - - - ranking = 0.086215147966308keywords = membrane (Clic here for more details about this article) |
10/116. Primary extracranial meningioma of the foot: a case report.We present a rare case of primary extracranial meningioma in a 36-year-old man, who had a solitary multinodular mass located in the plantar muscle of the foot. The histology of specimens from simple excision was typical of meningioma, showing bland spindle cell proliferation with a whorl pattern. Immunohistochemical analysis demonstrated that the tumor cells showed diffuse and strong positivity for epithelial membrane antigen as well as moderate reactivity for cytokeratin and vimentin. Ultrastructurally, the tumor cells were characterized by thin bipolar cytoplasmic processes and joined by multiple small desmosomes. There were frequent pinocytotic vesicles and a distinct external lamina on the cell surface. These findings suggest that this primary ectopic meningioma, arising in the soft tissue, may have been derived from perineurial cells of the peripheral nerve, but was morphologically distinguishable from perineurioma. Primary extracranial meningioma should be included in the differential diagnosis of soft-tissue spindle cell tumors, especially those of peripheral nerve origin.- - - - - - - - - - ranking = 0.086215147966308keywords = membrane (Clic here for more details about this article) |
| | Next -> |