1/6. 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 = giant (Clic here for more details about this article) |
2/6. Intravenous tufted angioma.A case of a rare vascular tumor, intravenous tufted angioma, is described. A 51-year-old Japanese man presented with a 12x8 mm solitary reddish nodule on the right foot, which had been found at birth. Histologically, the tumor was confined to a malformed vein and was characterized by nodular aggregates of plump cells. The aggregates showed a compact proliferation of round cells, including capillary-forming cells. Venous angiomatous areas were also observed. No multinucleated giant cells were seen. Immunohistochemically, the capillary-forming cells in the aggregates and the endothelial cells in the angiomatous areas were positive for endothelial markers (factor viii-related antigen, CD31, CD34). Pericyte-like cells expressing alpha-smooth muscle actin and muscle actin, and macrophage-like cells, which stained for factor xiiia, were intermingled in the cellular aggregates. Flow cytometric analysis showed diploidy. The tumor may be a hamartomatous lesion modified by secondary reactive changes, and it may represent a distinctive clinicopathological entity that is closely related histogenetically and perhaps pathologically to tufted angioma and the recently described "giant cell angioblastoma".- - - - - - - - - - ranking = 2keywords = giant (Clic here for more details about this article) |
3/6. Giant fetal hepatic hemangioma. Case report and literature review.The purpose of this case report is to demonstrate the importance of prenatal imaging for treatment management of fetal giant hepatic hemangiomas. Prenatal ultrasound revealed an abdominal mass with several cystic areas and punctate calcifications in a fetus at 29 weeks' gestation. Doppler scans confirmed the highly vascular nature of the mass. In this case, ultrasound diagnosed the mass was of hepatic origin, while magnetic resonance imaging at 32 weeks' gestation was more equivocal with respect to the anatomy source of the lesion. Imminent hydrops caused by a rapidly enlarged liver tumor was sonographically demonstrated at 34 weeks' gestation. An elective C-section and immediate tumor resection was performed. At the age of 20 months the infant is thriving. This case supports the notion that the survival rates for giant hepatic hemangiomas improve when fetal hydrops is averted and specific pre- and postnatal treatment is applied based on correct prenatal imaging diagnostics.- - - - - - - - - - ranking = 2keywords = giant (Clic here for more details about this article) |
4/6. Retroperitoneal Castleman's tumors of hyaline vascular type: imaging study. Case report.We report two retroperitoneal Castleman's tumors (giant lymph node hyperplasia) of hyaline vascular type. One was a large tumor situated in the pararenal region, the other was located in the pancreas head. On computed tomography (CT), both tumors were solid and moderately enhanced after administration of contrast material. On angiography, both tumors were hypervascular with dilated feeding arteries, and showed capillary blush. In an appropriate clinical setting, a retroperitoneal tumor showing these findings should include Castleman's tumor in the differential diagnosis.- - - - - - - - - - ranking = 1keywords = giant (Clic here for more details about this article) |
5/6. Tumor-induced osteomalacia and rickets.Tumor-induced osteomalacia is a clinicopathological entity in which vitamin d-resistant osteomalacia or rickets occurs in association with a tumor. A total of 72 cases (three current, 69 from review of literature) has been reported to date. Men and women are equally affected. The majority are adults over 30 years old who exhibit progressive lower leg and back pain. Forty bone and 31 soft-tissue tumors were responsible for this syndrome; two-thirds occurred in the extremities. Chemical findings are typical: low serum phosphorus, normal serum calcium, and elevated alkaline phosphatase. serum levels of 1,25-dihydroxyvitamin D were low or undetectable. Histologically, more than a third were classified as vascular tumors, and half of these cases were hemangiopericytomas that were distributed equally between bone and soft tissues. Other common diagnoses included nonossifying fibromas, "mesenchymal" and giant-cell tumor variants. Features common to all tumors were prominent vascularity, and giant and primitive stromal cells. Only 10 were histologically malignant. Ultrastructural studies have not shown any secretory granules suggestive of a hormone-secreting tumor. It is clear, however, that the tumor is responsible for the osteomalacia because the complete removal generally results in a dramatic reversal of all symptoms and signs.- - - - - - - - - - ranking = 2keywords = giant (Clic here for more details about this article) |
6/6. 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 = 1keywords = giant (Clic here for more details about this article) |