1/75. Malignant peripheral nerve sheath tumor arising in benign ancient schwannoma: a case report with an immunohistochemical study.A rare example of malignant transformation in an ancient schwannoma arising in the right side of the neck of a 51-year-old man without any clinical manifestations suggesting neurofibromatosis is described. The tumor, approximately 4 cm at its largest dimension, was well circumscribed and had a direct connection with the sympathetic nerve. Microscopically, the central portion of the tumor showed features of ancient schwannoma characterized by extensive hyalinization with cystic degeneration, scattered spindle cells with hyperchromatic and tapered nuclei, and some symplastic changes. However, predominantly in the outer portion, a proliferation of spindle-shaped cells with enlarged nuclei was present. The nuclei of these cells showed irregular contours, coarse granular chromatin texture, and conspicuous nucleoli. Mitotic figures and small necrotic foci with scattered apoptotic bodies were also seen. Immunohistochemically, S-100 protein was almost negative in areas consisting of overtly atypical cells where the mitotic index evaluated with MIB-1 antibody was 30.5%. In contrast, S-100-positive bland spindle cells were scattered in an extensively hyalinized area with a labeling index less than 3%. P53 protein was strongly positive in atypical spindle cells. Although it is a very uncommon event, definite nuclear atypia, frequent mitotic figures, and the existence of small necrotic foci should be recognized as indicating a diagnosis of malignant degeneration of benign schwannoma. immunohistochemistry would be useful as an ancillary technique in such a setting.- - - - - - - - - - ranking = 1keywords = spindle cell, spindle (Clic here for more details about this article) |
2/75. Ectopic hamartomatous thymoma: a case study and review of the literature.Ectopic hamartomatous thymoma is a rare and distinctive tumor found in the deep soft tissues of the neck, which is characterized histopathologically by a mixture of spindle, epithelial, and adipose cell elements. We present a case of this lesion occurring in a 39-year-old male. The characteristic histochemical and immunohistochemical findings of these tumors are demonstrated. In addition, review of the reported histological, immunohistochemical and ultrastructural findings is presented together with a table of clinical findings in the tumors so far described. A brief discussion of theories of histogenesis and possible differential diagnosis is included.- - - - - - - - - - ranking = 0.070323237427468keywords = spindle (Clic here for more details about this article) |
3/75. Cellular blue naevus of the scalp with brain invasion.A case of a 28 year old woman with an intracranial cellular blue naevus (CBN) which was believed to be the extension from a pigmented skin/scalp lesion is reported. There was no similar pigmented skin lesion noted on other parts of her body. Radical intervention, including wide excision of the affected skin of the scalp, removal of the underlying pigmented skull bone and wide excision of the pigmented dura, together with wide excision of the intracranial mass, were performed. The skin defect was covered by rotation flap and free skin graft. The dura was closed by grafting with fascia lata. The skull defect was left open and would be repaired later at a second planned surgery.- - - - - - - - - - ranking = 1.3918990197718keywords = naevus (Clic here for more details about this article) |
4/75. Glandular malignant peripheral nerve sheath tumor: an unusual case showing histologically malignant glands.In this report, we describe a highly unusual case of glandular malignant peripheral nerve sheath tumor presenting as a neck mass in a previously healthy 29-year-old man. Grossly, the tumor was found to arise from a swollen peripheral nerve trunk. The tumor was largely composed of spindle cells that demonstrated marked nuclear pleomorphism and numerous abnormal mitotic figures. In addition, histologically malignant glandular structures lined by simple nonciliated columnar cells with goblet cells were found clustered in the center of the tumor. Examination of the swollen peripheral nerve trunk revealed the presence of a plexiform neurofibroma. The spindle cells were positive for S100. The glands were negative for S100 but positive for keratin, epithelial membrane antigen, and neuroendocrine markers (somatostatin, chromogranin, Leu-7, and calcitonin). This patient was subsequently diagnosed as having von Recklinghausen disease and died of tumor metastasis to the lungs 34 months after the presentation. To our knowledge, only 3 similar cases have been previously described in the literature.- - - - - - - - - - ranking = 0.61978450838169keywords = spindle cell, spindle (Clic here for more details about this article) |
5/75. Juvenile hyaline fibromatosis in one Turkish child.We describe a case of juvenile hyaline fibromatosis (JHF) in a Turkish child. Only about 40 cases of juvenile hyaline fibromatosis had been reported in English literature as of March 1998, and it had not been reported in English literature from turkey as of November 1998. Juvenile hyaline fibromatosis characterized by multiple cutaneous masses is a rare hereditary disorder. This disease is usually found in children, and a malfunction of collagen synthesis is considered as the pathogenetic cause. In the presented case, light microscopy demonstrated an abundance of a homogeneous, amorphous, eosinophilic extracellular matrix in which fibroblasts were embedded. Well-formed collagen fibers could not be demonstrated with Gieson's method or with reticulin preparation. The hayalin material periodic acid-Schiff-positive and diastase-resistant, whereas the congo red method was negative. Immunohistochemically, the spindle-shaped cells were actin (smooth muscle) negative.- - - - - - - - - - ranking = 0.070323237427468keywords = spindle (Clic here for more details about this article) |
6/75. Non-nuchal-type fibroma associated with Gardner's syndrome. A hitherto-unreported mesenchymal tumor different from fibromatosis and nuchal-type fibroma.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.- - - - - - - - - - ranking = 0.070323237427468keywords = spindle (Clic here for more details about this article) |
7/75. Aggressive CD34-positive fibrous scalp lesion of childhood: extrapulmonary solitary fibrous tumor.Although solitary fibrous tumor (SFT) was originally described as a pleural tumor, an increasing number of extrapleural sites of SFTs have been documented. This has been attributed not only to the heightened awareness of the spectrum of histopathological features that characterizes SFTs but also to the recognition of the role of CD34 immunostaining in soft tissue tumors in general, and in SFTs in particular. Despite the large number of documented extrapleural SFTs in adults, cranial SFTs are rare, having been documented in the meninges, scalp, and infratemporal fossa. Extrapleural SFTs are, to date, an unrecognized entity in children. We document an aggressive fibrous scalp lesion in a 30-month-old female child that demonstrated features common to benign cranial fasciitis and SFT. However, based on bright, diffuse CD34 antigen immunopositivity, a diagnosis of SFT was made. The need to include the CD34 antigen stain in a panel of immunohistochemical markers used to assess spindle cell lesions of childhood is emphasized.- - - - - - - - - - ranking = 0.30989225419084keywords = spindle cell, spindle (Clic here for more details about this article) |
8/75. Spindle-cell B-cell lymphoma presenting in the skin.Lymphomas with predominant spindle-cell morphology have only been previously reported in small numbers; such lesions are potentially mistaken for sarcoma or other spindle-cell tumours. We describe a 73-year-old woman who presented with a tumour on the scalp of a few months' duration. biopsy showed a B-cell lymphoma of follicle centre cell origin with a sarcomatoid appearance and a CD20 , CD10 , CD21 , bcl-6 immunophenotype. This case highlights the very rare occurrence of spindle-cell B-cell lymphoma presenting in the skin. An awareness of this phenomenon is essential to avoid confusion with a variety of other cutaneous spindle-cell neoplasms and to enable a correct diagnosis to be made, thereby ensuring that appropriate treatment is initiated.- - - - - - - - - - ranking = 0.28129294970987keywords = spindle (Clic here for more details about this article) |
9/75. A case of head and neck kaposiform hemangioendothelioma simulating a malignancy on imaging.Kaposiform hemangioendothelioma (KH) is an endothelial-derived spindle cell neoplasm often associated with kasabach-merritt syndrome. Most cases arise in infancy and childhood and are soft-tissue tumors. The tumor displays an appearance between capillary hemangioma and Kaposi's sarcoma. We report a case of KH in a 1-year-old girl involving a mass that showed abnormal enhancement of soft tissue superficial to the right temporal bone with partial destruction of the temporal bone, the temporomandibular joint, mandibular condyle, and occipital bone. The physical finding of a discolored mass led clinicians to consider a hemangiomatous lesion, whereas the radiological picture suggested a more aggressive diagnosis of rhabdomyosarcoma and aggressive fibromatosis.- - - - - - - - - - ranking = 0.30989225419084keywords = spindle cell, spindle (Clic here for more details about this article) |
10/75. Benign glandular schwannoma.Glandular schwannoma is a rare variant of schwannoma characterized by the presence of glands in an otherwise typical schwannoma. We report a patient with benign glandular schwannoma occurring on the scalp, a site not previously reported. Histologically, a well-defined, encapsulated oval nodule was observed in the subcutaneous tissue. The nodule was composed of a spindle cell component and glandular structures. The spindle cell component stained positively for S-100 protein. All of the glandular epithelium stained with CAM 5.2 and epithelial membrane antigen but not with S-100 protein. The glandular epithelium was focally positive for carcinoembryonic antigen. The histogenesis of the glandular elements in these tumours is still debated. The variable size of the glandular structures in our case was evidence against an entrapped normal sweat gland origin. The glandular epithelium did not stain with S-100 protein at all, but stained with CAM 5.2, which did not support a direct metaplastic origin of the epithelial elements from the schwannian component. A few scattered CAM 5.2-positive cells and microglandular structures in our case may be the initial differentiating epithelial elements possibly derived from pluripotential neural crest cells.- - - - - - - - - - ranking = 0.61978450838169keywords = spindle cell, spindle (Clic here for more details about this article) |
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