1/108. 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 = 1keywords = antigen (Clic here for more details about this article) |
2/108. 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 = 1keywords = antigen (Clic here for more details about this article) |
3/108. Malignant fibrous histiocytoma after allogeneic bone marrow transplantation.A 24-year-old woman with CML underwent allogeneic BMT in August 1995 from a one-antigen HLA mismatched brother. Conditioning included BuCy2 and CsA and MTX were used to prevent GVHD. In July 1997 she developed right leg pain, lytic bone lesions of distal femur and a solid mass of soft tissue. Histological diagnosis of malignant fibrous histiocytoma was made. Despite treatment with surgery and chemotherapy (doxorubicin and ifosfamide), the patient died 1 year later with local recurrence of the tumor and liver, lung and brain metastases. The CML was in CR.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
4/108. 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 = 1keywords = antigen (Clic here for more details about this article) |
5/108. Extranodal peripheral T-cell lymphoma with angiocentric growth pattern and Epstein-Barr viral dna associated affecting paratesticular soft tissue.Peripheral T-cell lymphomas are uncommon, accounting for only 10% to 15% of all non-Hodgkin lymphomas and their classification has been controversial. We report a case of peripheral T-cell lymphoma with angiocentric growth pattern which presented as a paratesticular tumoral nodule in a 47-year-old-man. Formalin-fixed paraffin-embedded samples from the paratesticular tumor and non-infiltrated adjacent tissue were submitted to histological, immunohistochemical, polymerase chain reaction (PCR)-based and in situ hybridization analysis. Histopathologically, there was a lymphomatous infiltrate in the paratesticular soft tissue, composed of a variable mixture of medium-sized to large cells with large cytoplasm and irregular-shaped nuclei, together with blood vessel destruction, necrosis and karyorrhexis. Immunohistochemical study revealed a high p53 expression in neoplastic cells that showed T cytotoxic immunophenotype, failing to express the natural killer (NK)-cell antigen CD56. A monoclonal rearrangement of the T-cell receptor (TCR) gamma gene by a PCR technique was demonstrated. Type-A Epstein-Barr Virus (EBV) dna was detected by PCR-based analysis. A combined in situ hybridization and immunohistochemical study revealed that most cells labeled positive for EBV rna showed immunostaining with the CD45RO antibody. Based on the above results, the case reported was classified as extranodal peripheral T-cell lymphoma with cytotoxic phenotype and EBV associated. The present case does not fit neatly into any of the specific types of peripheral T-cell lymphomas of the REAL classification, so a diagnosis of peripheral T-cell lymphoma unspecified was made.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
6/108. Molecular characterization of SV40 dna in multiple samples from a human mesothelioma.BACKGROUND: Prolonged exposure to asbestos, a potent carcinogen, has been the generally accepted factor responsible for the development of human mesotheliomas. Recent reports documenting the detection of SV40 dna in human mesotheliomas suggest the possibility that this known tumor virus may be an additional factor involved in the development of some tumors. methods: A detailed analysis was performed by polymerase chain reaction and dna sequencing of the genetic characteristics of SV40 viral dna detected in samples taken from multiple sites of a human mesothelioma. RESULTS: A single virus variant was detected within the tumor that encoded a novel variable region at the C-terminus of the large T-antigen oncoprotein. The viral regulatory region was predominantly archetypal in sequence (lacking duplications of the enhancer), typical of natural isolates. CONCLUSIONS: These data confirm previous reports from several laboratories showing an association of SV40 dna with human mesotheliomas and provide the first evidence of a novel virus variant present in separated regions of a mesothelioma.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
7/108. Atypical presentation of hepatocellular carcinoma.Hepatocellular carcinoma is relatively rare in the united states, and the patterns of extrahepatic manifestations are diverse. disease dissemination occurs through hematogenous routes to frequently involve the lungs, bone, adrenal glands, and pancreas. Soft tissue metastasis is extremely rare and mandates systematic pathologic analysis, which may include the use of immunohistochemical staining for tumor-specific markers. Relevant tumor markers that can assist in localizing the site of origin for adenocarcinoma include carcinoembryonic antigen, alpha-fetoprotein, vimentin, and anticytokeratins. We detail the utility of immunohistochemistry in evaluating tumors of unknown origin.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
8/108. Fine needle aspiration and touch imprint cytology of a malignant fibrous histiocytoma of the spermatic cord. Case report.BACKGROUND: No cytologic reports on spermatic cord sarcomas have been published. CASE: A 64-year-old man presented with a slowly growing, painless, left spermatic cord enlargement. Fine needle aspiration (FNA) obtained < 1 mL of bloody fluid consisting of solitary, mark-edly anaplastic and pleomorphic tumor giant cells occasionally arranged in small fragments. Rare atypical spindle cells could be observed. Some reactive lymphocytes were observed intermingled with tumor cells. immunohistochemistry displayed vimentin reactivity and negativity for keratins and leukocytic common antigen. The specimen removed showed a well-circumscribed, 30-mm, yellowish solid tumor. touch imprints displayed pleomorphic tumor cells showing intense anisonucleosis; a moderate amount of clear, sometimes microvacuolated cytoplasm; and tissue fragments with a storiform pattern. Histologic examination revealed microscopic and immunohistochemical features of malignant fibrous histiocytoma (MFH) arising in soft tissues of the spermatic cord. CONCLUSION: FNA of a spermatic cord lesion may reveal a pleomorphic sarcoma. A pleomorphic appearance together with some spindle elements and compatible immunocytochemistry could help diagnose spermatic cord MFH. This is one of the few reports dealing with FNA cytology of paratesticular tumors and the first report, to the best of our knowledge, showing the cytologic characteristics of a case of spermatic cord MFH.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
9/108. 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 = 1keywords = antigen (Clic here for more details about this article) |
10/108. 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 = 1keywords = antigen (Clic here for more details about this article) |
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