1/4. Perivascular myoma: case report with immunohistochemical and ultrastructural studies.A subcutaneous myopericytoma-type perivascular myoma arising in the elbow of a 61-year-old woman is described. The tumor was well demarcated and consisted microscopically of small ovoid and spindle cells arranged in a concentric fashion, surrounding small to medium-sized vessels and imparting a superficial resemblance to hemangiopericytoma. In some areas, the cellular whorls were separated by myxoid stroma. cells located between cellular whorls appeared immature with scant cytoplasm but did not show distinct nuclear anaplasia, increased mitoses or foci of necrosis. immunohistochemistry showed that constituent cells were positive for alpha-smooth muscle actin and desmin. Electron microscopy disclosed that the immature-looking cells, as well as the ovoid and spindle-shaped cells, possessed focal densities along with thin filaments, subplasmalemmal densities, pinocytotic vesicles and an external lamina. These ultrastructural and immunohistochemical features indicate a myoid nature of pericytic cells and justify this type of neoplasm being categorized as perivascular myoid tumor.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
2/4. Carney's syndrome: complex myxomas. Report of four cases and review of the literature.Cardiac myxomas are rare tumors. They usually appear as a sporadic isolated condition in the left atrium of middle-aged women with no other coincidental pathology. Carney and others have described in young people a special complex group of cardiac myxomas associated to a distinctive complex pathology, giving identity to the "syndrome myxoma" or "Carney's syndrome". Four additional cases of this syndrome, treated from 1977 to 1999 at the Hospital Clinico de la Universidad de chile are presented here with a comprehensive review of the literature, accumulating 100 cases. The main features of our cases include the presence of malignant non cardiac tumors, a familial trend, follow-up of 23 years and an iterative recurrence in the elder case. To date all patients are tumor free. Reviewing the literature, patients with Carney's syndrome were younger, with a mean age of 26 years and female predominance (62%). Cardiac myxomas affected the four chambers of the heart: 64% the left atrium; 44% the right atrium; 14% the left ventricle and 12% the right ventricle. They were multiple tumors in 41% and involved more than one chamber in 31%, being synchronous or metachronous. There was a marked familial trend (52%), a high incidence of recurrence (20%), with more than one occurring in half the cases. Extra-cardiac involvement consisted of: 68% pigmented skin lesions, 40% cutaneous myxomas, 37% adrenal cortical disease, 27% myxoid mammary fibroadenoma and 34% male patients with testes tumors. A low percentage had pituitary adenoma, melanotic schwannomas and thyroid disease. The diagnosis is made when two or more of these criteria are present. In agreement with these findings the four chambers of the heart should be examined at surgery for atypical myxoma locations, right atriotomy and combined superior-transseptal approach improve exposure of the cavities, careful screening of the first degree family members should be conducted, and closed short and long term follow up controls are important. Complex myxoma appears as a multi-systemic disorder, occasionally having an ominous prognosis and malignant potentiality, and is still undergoing investigation for better understanding and identification.- - - - - - - - - - ranking = 2.9461345836219keywords = complex (Clic here for more details about this article) |
3/4. 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 = neoplasm (Clic here for more details about this article) |
4/4. Myopericytoma of the thoracic spine: a case report.STUDY DESIGN: A case of myopericytoma of the thoracic spine is reported. OBJECTIVE: To report a recently described and extremely rare soft tissue neoplasm in the previously unreported location of the thoracic spine. SUMMARY OF BACKGROUND DATA: Myopericytoma is a recently described soft tissue neoplasm with perivascular myoid differentiation. All cases have been reported in the subcutaneous and superficial soft tissues of the extremities. This represents the first reported case of this unusual lesion in the spine. methods: A patient with a 3-month history of progressive weakness of the arms and legs was found to have a lytic lesion of T3. The lesion was surgically treated by curettage followed by a course of radiation. Presenting symptoms, imaging studies, histologic findings, and related literature are reviewed in this study. RESULTS: Histologic evaluation of sections of the surgically removed lesion revealed a concentric, periluminal proliferation of cells with prominent positive smooth muscle actin immunoreactivity. These findings are consistent with the diagnosis of a myopericytoma, a lesion not previously reported in the spine. CONCLUSIONS: This study shows the presence of a lesion in the thoracic spine only previously described in the soft tissue of the extremities. The diagnosis of myopericytoma should be included, along with hemangiopericytoma, in the differential diagnosis of lytic lesions of the spine.- - - - - - - - - - ranking = 2keywords = neoplasm (Clic here for more details about this article) |