1/11. Myoepitheliomas of the skin and soft tissues. Report of 12 cases.We describe 12 cutaneous and soft tissue myoepitheliomas, most of them in elderly patients. Morphologically the cutaneous and soft tissue myoepitheliomas revealed the same spectrum as their salivary gland counterparts. They were composed of a mixture of spindle, epithelioid and clear myoepithelial cells. Immunohistochemically they were positive to keratins and S-100 protein and reacted inconsistently with antibodies to smooth muscle actin. Morphologically they lacked any folliculo-sebaceous or apocrine differentiation. We believe that they are related to the eccrine type of cutaneous mixed tumours. Most cases had a benign behaviour, but 1 tumour metastasized, and the patient died of the tumour. Myoepitheliomas of soft tissues should be distinguished from other neoplasms with epithelial differentiation and from ossifying fibromyxoid tumour of soft parts, parachordoma and extraskeletal myxoid chondrosarcoma.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
2/11. Myofibroblastic tumours: neoplasias with divergent behaviour. Ultrastructural and flow cytometric analysis.myofibroblasts are spindle cells having ultrastructural features in common with smooth muscle cells and fibroblasts. In the last few years, tumours have been described in which myofibroblasts represent not only a reactive mechanism but also a true neoplastic component. They constitute new nosologic entities which might be termed "myofibroblastic tumours". Tumours with benign and, rarely, malignant behaviour are reported to belong to this group of lesions. Recently, a third tumour type with borderline biological course, named "inflammatory myofibroblastic tumour" (IMT), has been identified, a condition that has been regarded as a benign and reactive disorder for a long time. Only in recent reports has been demonstrated that, in spite of an apparently benign morphological pattern, some cases of IMT have a malignant course. In this connection, dna analysis by flow cytometry is a valuable diagnostic tool, because it allows identification of the ploidy status, a procedure that is often useful for predicting the nature and the biological behaviour of the lesion. In this study, 11 cases of myofibroblastic tumours were examined retrospectively by evaluating clinicopathological features and dna ploidy status by flow cytometry. The diagnosis of myofibroblastic tumour was confirmed by performing histology, immunohistochemistry, and electron microscopy in all patients. In detail, these 11 cases were composed of 1 benign myofibroblastoma, 1 myofibrosarcoma and 9 IMTs. Among these myofibroblastic tumours, all those with local recurrence or distant metastases (one myofibrosarcoma and three IMT) showed an aneuploid cell population demonstrable by flow cytometric analysis, whereas the other cases with benign course (one benign myofibroblastoma and six IMT) exhibited an euploid dna content. These data suggest the following: a) Besides the rare myofibroblastomas and myofibrosarcomas, IMTs represent a larger group of lesions with potentially different biological and clinical course. b) dna flow cytometric analysis is a reliable tool that support histopathological examination in characterizing those cases of IMT that, though being malignant, mimic benign lesions. Consequently, it establishes the basis for a different therapeutic approach according to the euploid or aneuploid dna content.- - - - - - - - - - ranking = 6keywords = behaviour (Clic here for more details about this article) |
3/11. Congenital infantile fibrosarcoma of the upper extremity.Congenital-infantile fibrosarcoma is an unusual childhood tumor that occurs mainly in children under 5 years of age. More than 300 cases have been reported in the literature so far, very few of them at birth. A distinction must be made between it and its adult counterpart because of differences in their clinical behaviour. We report here a case of congenital fibrosarcoma in a 4-day-old female infant.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
4/11. Solitary fibrous tumour in the deep soft tissue of the neck in a Chinese man.Originally described in the pleura, solitary fibrous tumour (SFT) is now reported in a variety of extrapleural sites. However, description of SFT in the deep soft tissue of the neck is very rare. In this report, we document the neoplasm, deep to the right platsyma muscle but superficial to the deep fascia just above the clavicle, in an otherwise well 50-year-old Chinese man. Histological examination of the excised specimen disclosed spindle-shaped cells disposed in short fascicles as well as randomly in association with areas of varying cellularity, keloidal hyalinisation of the stroma and haemangiopericytoma-like vessels. The tumour cells were CD34-, bcl-2- and CD99-positive. Since histological features may not accurately predict the biological behaviour of this tumour, careful long-term follow-up is advocated.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
5/11. Malignant myopericytoma: expanding the spectrum of tumours with myopericytic differentiation.AIMS: The spectrum of tumours showing myopericytic differentiation is increasingly being defined and includes lesions such as myofibroma and infantile haemangiopericytoma. Here we seek to describe for the first time and clinicopathologically characterize examples of malignant myopericytoma. methods AND RESULTS: Five cases of malignant myopericytoma were identified in the authors' consultation files. Immunostains were performed and clinical information was obtained. Tumours arose in three females and two males (median age 67 years, range 19-81 years) on the neck, arm, thigh and foot. One patient presented with disseminated metastases. One patient had a prior history of multiple benign myopericytomas in the same location. Four patients developed metastases and three died within 1 year. Tumours were composed of highly mitotic myoid-appearing ovoid-to-spindle cells showing at least focally striking perivascular orientation resembling that seen in benign myopericytoma; three cases were focally fascicular and three showed thin-walled branching vessels. All tumours showed at least focally prominent positivity for smooth muscle actin. One case showed dot-like desmin positivity. CONCLUSIONS: In reporting examples of malignant myopericytoma, we further characterize and broaden the morphological spectrum of myopericytic neoplasms. Available data indicate that malignant myopericytomas are associated with aggressive clinical behaviour.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
6/11. Metastasising congenital subcutaneous sacrococcygeal ependymoma.A case of myxopapillary ependymoma located subcutaneously in sacrococcygeal area of a 18 months male child with metastasis to right inguinal lymph nodes is described; the tumour was present since birth. Histological examination of the tumour besides myxopapillary structures, also revealed an ependyma lined cystic space, resembling ventricular cavity. So far only two cases of congenital metastasising subcutaneous sacrococcygeal ependymoma have been described. However, the present case had a very aggressive post-operative biological behaviour.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
7/11. Interdigitating dendritic cell sarcoma: a report of four paediatric cases and review of the literature.AIMS: To report a series of four paediatric cases of interdigitating dendritic cell sarcoma (IDCS) and add to the known extranodal sites of occurrence for this tumour. neoplasms derived from interdigitating dendritic cells are rare, with only 33 cases being reported in the literature (medline search). These tumours usually occur in lymph nodes in the adult population. methods AND RESULTS: The patients were a 10-year-old girl with a large soft tissue mass bulging into the left chest, a 12-year-old girl with a right paraspinal mass, a 21-month-old boy with generalized lymphadenopathy and hepatosplenomegaly and a 6-year-old girl with a large bladder mass. paraffin blocks and haematoxylin and eosin slides were available in all cases. In addition, immunohistochemistry and electron microscopy were performed. A diagnosis of IDCS was made in all cases. CONCLUSION: The diagnosis of IDCS can rarely be entertained on clinical information alone. Microscopically, there is a wide spectrum of features. Thus, immunohistochemistry and electron microscopy are crucial in making the diagnosis. The differential diagnosis includes inflammatory pseudotumour, follicular dendritic cell sarcoma, true histiocytic lymphoma, malignant Langerhans cell histiocytosis, anaplastic large-cell lymphoma, melanoma, and a range of sarcomas. IDCS displays aggressive behaviour and approximately half of the patients die of the disease.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
8/11. Clear cell sarcoma (malignant melanoma of soft parts) and sentinel lymph node biopsy.Clear cell sarcoma of the tendons and aponeuroses is an aggressive, rare soft tissue tumour that occurs predominantly in the extremities of young adults. Although it appears to be histogenetically related to melanoma, its clinical behaviour resembles soft tissue sarcoma. prognosis is reported to be poor due to the great propensity of regional and distant metastases. The risk of metastases to regional lymph nodes is very high. We describe a case of clear cell sarcoma of the hand and evaluate the feasibility of the sentinel lymph node biopsy (SLNB) technique in this kind of tumour. Up to now, there are no reports that describe the use of SLNB in clear cell sarcoma. The SLNB technique was carried out with success and the sentinel lymphnode was easily identified. Histological examination of the lymphnode allowed identification of metastatic cells and thus provide for radical lymphadenectomy. We maintain that SLNB can be successfully used for this type of tumour although this result should be evaluated and confirmed by larger case studies.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
9/11. Plexiform fibrohistiocytic tumor: three unusual cases occurring in infancy.BACKGROUND: Plexiform fibrohistiocytic tumor is a soft-tissue tumor of intermediate malignancy occurring in children and young adults but is only rarely found in infants. The tumor usually involves the upper limbs and is slow growing and painless. recurrence rate is high. Lymph node and systemic metastases can occur, but have never been reported in infants. Clinical behavior in infancy is not known. Histologically, the tumor is characterized by nodules of histiocyte-like and multinucleated cells and fascicles of spindle cells arranged in a plexiform pattern. mitosis, atypia, and nuclear pleomorphism are common but not pronounced. methods AND RESULTS: We report three cases in infants, one of which is congenital, having an unusual topography and a broad histological spectrum. CONCLUSION: In infants, wide excision with large safety margins should be performed as the behaviour of this tumor remains uncertain. Leclerc S, Hamel-Teillac D, Oger P, Brousse N, Fraitag S. Plexiform fibrohistiocytic tumor: three unusual cases occurring in infancy.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
10/11. Congenital fibrosarcoma: presence of a histiocytic component.We describe the histologic and ultrastructural appearance of a massive soft-tissue tumor in the left lower extremity of a newborn girl. In its clinical presentation and morphologic features, this tumor corresponded to the entity currently known as congenital fibrosarcoma. The variability of histologic conformation of these lesions is emphasized. Ultrastructural study disclosed many cells with the subcellular morphology of elements of the histiocytic-macrophagic series. Whether these cells are viewed as an integral part of the tumor or as a secondary feature, their presence in a congenital fibrosarcoma is of interest for understanding of biologic behaviour of these uncommon tumors.- - - - - - - - - - ranking = 1keywords = behaviour (Clic here for more details about this article) |
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