1/10. Epithelioid cell histiocytoma: a simulant of vascular and melanocytic neoplasms.Epithelioid cell histiocytoma (ECH) is an unusual and still poorly recognized variant of benign fibrous histiocytoma. Epithelioid cell histiocytoma differs from most benign fibrous histiocytomas in five important ways: the predominance of epithelioid cells, relative lack of secondary elements (such as giant cells, foamy, or hemosiderin-laden macrophages), relative sharp circumscription, prominent vascularity, and centering in the papillary dermis in most cases. A strong resemblance to melanocytic and vascular lesions has been noted, and a recent case was reported with features suggesting endothelial origin. Fifteen new cases of ECH, including one example of the rare deep cellular variant, are presented herein, with emphasis on features mimicking vascular and melanocytic neoplasms. Labeling with endothelial markers, including previously unreported CD-31 labeling, showed abundant vascular staining, which may be challenging to interpret, but which does not indicate an endothelial origin of ECH.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
2/10. Benign vascular neoplasms of the spleen with myoid and angioendotheliomatous features.AIMS: To present the clinical light microscopic and immunophenotypic features of a distinctive vascular neoplasm of the spleen. methods AND RESULTS: Two of the splenic lesions arose in children, and one was found in an adult. They ranged from 19 to 40 mm diameter and histologically were quite similar. Sheets of large epithelioid cells with a spectrum of nuclear configurations ranging from oval and vesicular to twisted and hyperchromatic were noted in each case. Distinct or prominent nucleoli were present in many cells, and occasional cells had nuclear pseudoinclusions. In two cases, bands of basophilic, fibroblast-rich stroma with scattered chronic inflammatory cells were present. The mitotic rate ranged from 0/10 high-power fields (HPF) to 0.5/10 HPF in these epithelioid cells. The vascular nature of these tumours was manifested as a sieve-like array of round, erythrocyte-filled spaces, most with attenuated and cytologically bland lining cells. The polygonal, epithelioid cells exhibited the following phenotype: smooth muscle actin (SMA) , muscle specific actin (MSA) , vimentin , CD31-, CD34-, CD21-, CD8-, CD68- (2/3 cases), S100-, while the lining cells were CD34 , vimentin and SMA-, with variable CD31 and factor viii related antigen expression. Elongated SMA , MSA cell processes were evident in one case, reminiscent of previously characterized myoid elements of the normal spleen. An uneventful follow-up was noted for all three patients. CONCLUSIONS: The histology and immunophenotype set these neoplasms apart from classic hamartomas, haemangiomas and previously characterized (haem)angioendotheliomas of the spleen, and may represent proliferations of myoid elements native to the spleen.- - - - - - - - - - ranking = 1.2keywords = neoplasm (Clic here for more details about this article) |
3/10. 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 = 0.2keywords = neoplasm (Clic here for more details about this article) |
4/10. Fulminant intravascular lymphoma presenting as fever of unknown origin.Intravascular large cell lymphoma (IVLL) is a rare neoplasm characterized by the proliferation of malignant lymphoid cells within the lumens of small to medium-sized blood vessels. The central nervous system, skin, and endocrine systems are most commonly involved. IVLL may disseminate to the heart, pancreas, liver, spleen, kidneys, and adrenal glands. We report a 52-year-old patient who was admitted for fever of unknown origin for 3 weeks, jaundice and abnormal liver function tests. Fever, high levels of bilirubin, severe anemia, thrombocytopenia, and a very fulminant course characterized the clinical picture. Although bone marrow involvement is quite rare, the diagnosis of IVLL in this patient was done by bone marrow biopsy. The patient was treated with CHOP protocol and received the first course but the aggressive disease led to the patient's death.- - - - - - - - - - ranking = 0.2keywords = neoplasm (Clic here for more details about this article) |
5/10. Clinicopathological features of unusual vascular lesions of the pelvis, retroperitoneum and colon in females: a report of five cases and review of the literature.Vascular lesions comprise benign and malignant neoplasms as well as non-neoplastic conditions that may be located in various sites but only rarely in the pelvis or the retroperitoneum. In our study we describe five diverse and unusual cases of vascular lesions of the pelvis, retroperitoneum and colon in female patients: a case of retroperitoneal angiosarcoma, pelvic hemangioendothelioma, pelvic angiomyxoma, retroperitoneal lymphangioleiomyomatosis and a case of diffuse cavernous hemangiomatosis of the colon, with emphasis on their clinicopathological features and differential diagnosis. The recent literature on the subject is also briefly reviewed.- - - - - - - - - - ranking = 0.2keywords = neoplasm (Clic here for more details about this article) |
6/10. Cervical carotid artery dissection secondary to malignant fibrous histiocytoma.A rare case of malignant fibrous histiocytoma of the cervical carotid artery is presented. Erosion of the vessel wall by this neoplasm resulted in dissection and pseudoaneurysm formation. The etiology and diagnosis of and the therapeutic alternatives for this unique disorder are discussed briefly.- - - - - - - - - - ranking = 0.2keywords = neoplasm (Clic here for more details about this article) |
7/10. Primary undifferentiated sarcoma of the thoracic aorta.A case of a primary undifferentiated sarcoma of the descending thoracic aorta in a 75-year-old man is reported. Intraluminal growth and occlusion produced congestive heart failure and renal failure. The thoracic aorta was relatively normal on chest radiography so that the lesion was undiscovered until the autopsy. To our knowledge, it is the first case of a primary undifferentiated sarcoma of the thoracic aorta, and the first undifferentiated aortic sarcoma to be examined with immunohistochemistry and electron microscopy. Electron microscopy and immunohistochemistry verified the sarcomatous nature of the undifferentiated neoplasm.- - - - - - - - - - ranking = 0.2keywords = neoplasm (Clic here for more details about this article) |
8/10. Malignant endothelial neoplasm arising in the area of lymphangioma: immunohistochemical and ultrastructural observation.This report presents a rare malignant endothelial neoplasm which arose at the site of a pre-existing lymphangioma. The lymphangioma was located on the right buccal mucosa, and the malignant neoplasm arose 17 years after irradiation of the initial tumor. Clinical, light microscopic and immunohistochemical (factor viii-related antigen and ulex europaeus Agglutinin-I) studies were made, together with observations by transmission and scanning electron microscopy. These studies provide evidence that this malignant neoplasm was well-differentiated and had not yet lost the characteristics of normal lymphatic cells.- - - - - - - - - - ranking = 1.4keywords = neoplasm (Clic here for more details about this article) |
9/10. Exuberant granulation tissue mimicking vascular tumours associated with burns.A case of simultaneous development of multiple vascular neoplasms in a patient with a previous history of burns and lymphoblastic lymphoma is reported. Microscopic examination revealed angiomatosis made up of diffuse capillary proliferation. We speculate that endogenous factors could have played an important role in the development of these neoplasms. We discuss the clinical and histological differential diagnosis of the case presented: a disseminated variant of lobular capillary haemangioma, Kaposi's sarcoma, bacillary angiomatosis and hyperplastic granulation tissue.- - - - - - - - - - ranking = 0.4keywords = neoplasm (Clic here for more details about this article) |
10/10. Aneurysmal benign fibrous histiocytoma: clinicopathological analysis of 40 cases of a tumour frequently misdiagnosed as a vascular neoplasm.Forty cases of the distinctive but poorly recognized aneurysmal variant of cutaneous fibrous histiocytoma are described. These tumours presented most commonly in middle-age adults, with a slight predilection for females. Anatomical distribution was wide with most cases occurring in the lower limb/limb girdle (50%), upper limb/limb girdle (20%) and trunk (17%). Lesional size ranged from 0.5 cm to 4 cm. Haemorrhage accounted for the rapid clinical growth of some lesions and the frequent clinical confusion with a cyst, a melanocytic lesion or a haemangioma. Five (19%) of the twenty-six cases with follow-up (mean duration 2.5 years) recurred locally, twice in two cases. One of these cases had involvement of a regional lymph node in the second recurrence, most likely as a result of direct local extension. Distinctive histological features were prominent blood-filled spaces, varying from artefact-like clefts to cystic areas mimicking cavernous vascular channels but devoid of an endothelial lining, prominent haemosiderin deposition, numerous siderophages and giant cells, and a moderate mitotic rate. Despite the presence of prominent secondary changes due to haemorrhage, all cases showed cellular polymorphism, hyalinized collagen bundles surrounded by tumour cells in the periphery of the lesion and 88% showed some degree of epidermal hyperplasia, as seen in common fibrous histiocytoma. immunohistochemistry (ABC method) revealed only vimentin and, rarely, focal smooth muscle actin positivity. CD68 was positive in some reactive macrophages only. Stains for CD31, CD34, desmin and factor xiiia were negative in all cases tested.(ABSTRACT TRUNCATED AT 250 WORDS)- - - - - - - - - - ranking = 0.8keywords = neoplasm (Clic here for more details about this article) |
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