1/65. Solitary malignant peripheral nerve sheath tumor of the pancreas.Primary malignant peripheral nerve sheath tumors of the pancreas are rare. This is a report of a 72 year-old African male who presented with an 8 lb. weight loss and anorexia. A computed tomography (CT) scan revealed a 12 cm mid pancreatic mass. An 85% pancreatectomy (with splenectomy) was performed. Immunohistopathologic and ultrastructural (electron microscopy) evaluation established the schwann cell origin of this neoplasm. The clinical management and pathologic findings are discussed in this report as well as a review of the literature.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
2/65. Molecular analysis of malignant triton tumors.Triton tumors are rare variants of malignant peripheral nerve sheath tumor (MPNST) with muscle differentiation, often seen in patients with neurofibromatosis 1 (NF1). Individuals affected with NF1 harbor mutations in the NF1 tumor suppressor gene and develop neurofibromas and MPNSTs. The NF1 gene is expressed in schwann cells and its expression is lost in schwannian neoplasms, suggesting a role in malignant development. Separately, there is evidence that p53 suppressor gene mutations are involved in MPNSTs. To determine the role of the NF1 and p53 genes in the development of the malignant Triton tumor we examined 2 such tumors, 1 from a 3-year-old boy without clinical manifestations of NF1 and another from a 24-year-old man with NF1. Histological analysis of these tumors showed both neural and muscle differentiation with S-100 and desmin immunoreactivity, respectively. Reverse transcribed rna polymerase chain reaction (RT-PCR) of NF1 mRNA showed NF1 expression in the sporadic tumor. Strong nuclear immunoreactivity for p53 was observed throughout the malignant population in both tumors. This was confirmed by loss of heterozygosity for p53 in the non-NF1 patient, suggesting that p53 is involved in both hereditary and sporadic Triton tumors. The finding of preserved NF1 gene expression in the non-NF1-related Triton tumor suggests that different genetic events predispose to the development of this rare neoplasm in sporadic cases.- - - - - - - - - - ranking = 2keywords = neoplasm (Clic here for more details about this article) |
3/65. Malignant intracerebral nerve sheath tumor with intratumoral calcification. Case report.The authors present the clinical, radiological, and pathological features of a malignant intracerebral nerve sheath tumor that occurred in the right parietooccipital lobe of a 4-year-old girl. Computerized tomography scanning and magnetic resonance imaging demonstrated a 5x5x4-cm multiloculated mass with considerable enhancement of the irregularly shaped septa and clearly calcified areas within the mass. Among five cases reported in the literature, this patient is the youngest and represents the first case in which there is radiological evidence of intratumoral calcification.- - - - - - - - - - ranking = 0.0012551689553594keywords = cerebral (Clic here for more details about this article) |
4/65. carcinosarcoma of the urinary bladder--an aggressive tumor with diverse histogenesis. A clinicopathologic study of 4 cases and review of the literature.OBJECTIVE: Carcinosarcomas of urinary bladder are rare malignant neoplasms. Seventy-eight cases have been previously described. The histologic composition of these tumors is variable, but diagnosis requires the presence of both epithelial and mesenchymal malignant components. We report 4 additional cases, with an emphasis on unusual histologic features. methods: Histologic and immunohistochemical examinations were performed on bladder tumors from 4 patients. Clinicopathologic features of previously reported and current cases were reviewed and summarized. RESULTS: Four patients (3 men, 1 woman) age 54 to 77 years were found to have polypoid masses in the urinary bladder. In all cases, histologic examination showed biphasic neoplasms with distinct mesenchymal and epithelial components. The morphologic and immunohistochemical characteristics of the tumors varied. One of the cases was remarkable for the presence of liposarcoma, malignant peripheral nerve sheath tumor, and micropapillary urothelial carcinoma. Two of the patients died 2 years after diagnosis, which is consistent with the previously reported aggressive nature of urinary bladder carcinosarcomas. CONCLUSIONS: Carcinosarcomas of the urinary bladder are rare, aggressive malignant neoplasms. To our knowledge, a liposarcomatous component has been reported in only 1 case previously, and components of micropapillary urothelial carcinoma and malignant peripheral nerve sheath tumor have not been reported previously in carcinosarcomas of the urinary bladder. Because of the aggressive biologic behavior of these tumors, they should be identified promptly and treated appropriately.- - - - - - - - - - ranking = 3keywords = neoplasm (Clic here for more details about this article) |
5/65. Fine-needle aspiration cytology and core biopsy of malignant peripheral nerve sheath tumor of the uterus: a case report.Malignant peripheral nerve sheath tumor (MPNST) is an uncommon mesenchymal neoplasm of neural origin. MPNST arising in the uterus is extremely rare. Its histologic appearance on this anatomical location has been only rarely reported. A 62-yr-old woman with a previous history of partial hysterectomy presented with a large pelvic mass in the uterine stump. Fine-needle aspiration (FNA) and core biopsy were obtained under ultrasonographic guidance, and the diagnosis of MPNST was established. The cytologic and histologic findings were consistent with a spindle-cell neoplasm suggestive of MPNST. The tumor cells were focally positive for S-100 protein immunostain, thus providing further support for the neoplasm's nerve sheath differentiation. The patient had no history of von Recklinghausen's disease. Resection of the mass confirmed the diagnosis of MPNST. To our knowledge, the FNA cytology of MPNST in this unusual location has not been previously reported. FNA cytology, along with core biopsy and immunochemistry, is a reliable tool in the diagnosis of MPNST.- - - - - - - - - - ranking = 3keywords = neoplasm (Clic here for more details about this article) |
6/65. sciatica due to malignant nerve sheath tumour of sciatic nerve in the thigh.Malignant peripheral nerve sheath tumour (MPNST) is a rare malignant neoplasm arising from the supportive non-neural component of the peripheral nerves. An unusual case of pain and weakness of the foot and calf muscles due to a giant MPNST of the sciatic nerve in the posterior compartment of the thigh is presented. The patient was already investigated as a case of sciatica due to a lumbar disc disease with a negative magnetic resonance imaging and then unsuccessfully operated elsewhere twice, with a misdiagnosis of tarsal tunnel syndrome. Neurosurgical referral prompted a diagnostic magnetic resonance study of the thigh, revealing the lesion, which was completely excised microsurgically with total relief in the pain and partial improvement in the weakness and sensations in the sole of the foot.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
7/65. Cutaneous sclerosing Pacinian-like perineurioma.AIMS: The term perineurioma has been used to designate a variety of clinically and histologically different proliferations of perineurial cells based on immunohistochemical and/or ultrastructural characterization. There are two different groups of neoplasms derived from perineurial cells: extraneural or soft tissue perineuriomas, and intraneural perineuriomas. Recently, a sclerosing variant of cutaneous perineurioma has been described. methods AND RESULTS: We report a case of a cutaneous form of perineurioma, combining features of the intraneural and sclerosing varieties, as well as showing a Pacinian pattern of growth. In order to assess the neoplastic nature of the lesion, we performed fluorescence in-situ hybridization (FISH) analysis using a probe which maps to the chromosome band 22q11 and 22q13, allowing us to show deletion or loss of one chromosome 22 in the tumour cells. CONCLUSIONS: This case may be considered a new variant of perineurioma with Pacinian-like features, for which we propose the designation 'sclerosing Pacinian-like perineurioma'.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
8/65. Intrarenal solitary fibrous tumor of the kidney report of a case with emphasis on the differential diagnosis in the wide spectrum of monomorphous spindle cell tumors of the kidney.Solitary fibrous tumor (SFT) is a neoplasm that can occur in the urogenital tract, and is also reported occurring in the spermatic cord, seminal vesicles, urinary bladder, prostate, and kidney. Furthermore, it is most important to consider its existence in the kidney, because it is usually diagnosed as renal cell carcinoma pre-operatively. To our knowledge, only 10 cases of SFT have been reported in the kidney to date. We report the clinico-pathological features of an intrarenal SFT occurring in a 31-year-old woman. The tumor, measuring 8.6 cm in its greatest diameter, completely replaced the cortex and the medulla of the middle region of the right kidney, compressing the pelvis. Radiological imaging was consistent with a renal cell carcinoma. Histologically, the tumor was composed of a proliferation of bland-looking vimentin , CD34 , bcl2 and CD99 spindle cells exhibiting a haphazard to storiform growth pattern, pushing borders, and a low mitotic rate (2 mitoses x 10 HPF). We placed emphasis on the differential diagnostic problems, i.e., its differentiation from other primary monomorphous benign and malignant spindle cell tumors of the kidney, such as fibroma, benign fibrous histiocytoma, hemangiopericytoma, inflammatory myofibroblastic (pseudo-)tumor, leiomyoma, angiomyolipoma with predominant spindle cell smooth muscle component, benign peripheral nerve sheath tumors, renal mixed epithelial/stromal tumors, adult type mesoblastic nephroma, fibrous type monophasic synovial sarcoma, malignant peripheral nerve sheath tumors, fibrosarcoma, and low-grade fibromyxoid sarcoma.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
9/65. Nerve cell markers in ossifying fibromyxoid tumour of soft parts.Reported herein are two benign ossifying fibromyxoid tumors (OFMTs) of the soft tissues in axilla and terminal phalanx respectively. Both cases on immunohistochemistry (IHC) showed reactivity for vimentin, S-100 protein and glial fibrillary acidic protein (GFAP) antibodies. In addition, a focal/diffuse strong positivity for neurofilament (NF) and neuron specific enolase (NSE) was observed. Electron microscopy in one instance revealed abundant intermediate filaments, primitive cell junctions and a focally present external lamina. In the light of nerve cell differentiation of these tumors and the similarity of IHC profile and EM features of OFMT to a poorly differentiated malignant peripheral nerve sheath tumor (MPNST); it is suggested that OFMT is a variably differentiated PNST rather than a simple Schwannian neoplasm as is believed.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
10/65. Cardiac sarcoma showing bone formation and neurogenic markers: report of a case.A 54 year-old Japanese female with cardiac insufficiency was found to have a left atrial mass and smaller masses on the mitral valve. Excisional surgery of the masses and mitral valve replacement were carried out. In spite of intensive post-operative radiation therapy, the patient died of intra-atrial recurrence and brain metastases after 8 months. Tumour cells were spindled to oval, were positive for vimentin, S100 protein and neurone specific enolase. laminin and fibronectin were also demonstrated. Bone formation and myxoid areas were present. An ultrastructurally identifiable stromal component, possibly responsible for laminin and fibronectin staining, was also present. The merits of the two main diagnostic possibilities - a mesenchymal/fibroblastic sarcoma showing bone and aberrant S100 protein, and a malignant peripheral nerve sheath tumour with bone - were discussed. In practical terms, the tumour was given the diagnosis of unclassifiable sarcoma of the left atrium. Atrial sarcomas showing neural markers and bone formation are exceedingly rare, and this report adds a further exceptionally uncommon case to the literature.- - - - - - - - - - ranking = 0.00051866249266641keywords = brain (Clic here for more details about this article) |
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