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1.
We report herein the case of a 77-year-old man with a left ventricular tumor originating from the papillary muscle of the left ventricular wall, in whom a successful tumor resection with mitral valve replacement was performed. The pathological diagnosis of the tumor was confirmed as cardiac fibroma. His postoperative course was uneventful and he is currently well with no signs of recurrence 2 years after surgery.  相似文献   
2.
非骨化性纤维瘤的X线平片与CT诊断   总被引:2,自引:0,他引:2       下载免费PDF全文
目的:评价X线平片和CT扫描在诊断长骨非骨化性纤维瘤中的作用,旨在提高对该病的诊断与鉴别诊断水平。方法:对16例经手术病理证实的非骨化性纤维瘤的X线平片和CT特征进行回顾性分析。结果:肿瘤部位为胫骨9例,股骨6例,腓骨1例。肿瘤形态为卵圆形,肿瘤的长径2.0~8.0cm,肿瘤边缘均有硬化边。根据X线平片及CT所见分为2型:皮质型或偏心型(12例)和骨髓型或中心型(4例)。讨论:非骨化性纤维瘤的X线平片和CT表现具有特征性,对诊断和鉴别有重要作用。  相似文献   
3.
Ritschl  P.  Karnel  F.  Hajek  P. 《Skeletal radiology》1988,17(1):8-15
The radiomorphological appearance of fibrous metaphyseal defects (FMDs) is demonstrated by long-term follow-up studies. A characteristic radiomorphological course rather than a typical single appearance can be established. These findings correlate well with the duration of these tumor-like lesions; therefore, the radiological findings allow conclusions to be made about the age of a fibrous metaphyseal defect. In addition, the characteristic locations of FMDs will be explained in respect of their origins at insertions of tendons and ligaments.  相似文献   
4.
The case describes a 38-year-old woman presenting a multilocular radiolucency affecting the entire right half of the lower jaw, with an unerupted third molar displaced to the region of the coronoid process. The histological study showed the presence of fibroblasts, focally with pleomorphic nuclei, dense collagen and an odontogenic epithelium with dystrophic calcifications. A cyst with an important inflammatory infiltrate was, moreover, observed.  相似文献   
5.
Since peripheral odontogenic fibroma (POF) is characteristically described as a solitary lesion and no diffuse POF had been reported in the literature, our cases should be considered as extremely unusual. Three diffuse cases of POF are described of which one case was seen in association with ocular and skin lesions. The question arises whether POF should be considered as a true odontogenic tumor rather than a diffuse hamartomatous lesion caused by uncontrolled induction of the gingiva. It is also possible that such lesions could be part of a yet undescribed syndrome.  相似文献   
6.
7.
Chondromyxoid fibroma is a rare benign cartilaginous bone tumour characterized by morphological features that resemble different steps of chondrogenesis in terms of both cellular morphology, ranging from spindled to rounded cells, and the extracellular matrix formed, which ranges from fibrous to cartilaginous. The presence in chondromyxoid fibroma of signalling molecules that regulate the spatial expression of proteins involved in normal cartilage proliferation and differentiation was investigated in samples from 20 patients and compared with articular chondrocytes from 11 normal donors cultivated in 3D pellet culture. Sections were stained with safranin-O and H&E, and immunohistochemistry was performed for p16, cyclin D1, FGFR3, BCL2, p21, PTHLH, PTHR1 and N-cadherin. Expression patterns were analysed using hierarchical clustering. In chondromyxoid fibroma, specific morphological features correlated with a distinct pattern of expression. Comparison with normal chondrocytes in pellet culture showed a striking morphological resemblance, but with an unmistakably different pattern of expression. N-cadherin, PTHLH, and PTHR1 were expressed to a significantly higher level (p < 0.01) in articular chondrocyte pellets but, conversely, there was significantly lower expression of cyclin D1, p16 and BCL2 (p < 0.05) in these cells. Morphological similarities reflect common steps in cartilage differentiation, albeit driven by different molecular mechanisms. The proteins we have found to be differentially expressed seem crucial for neoplastic chondrogenesis.  相似文献   
8.
The ameloblastic fibrosarcoma is a rare variety of neoplasm. Three new cases reported here occurred within preexistent benign odontogenic tumors (ameloblastic fibroma or fibro-odontoma). These large, osteolytic tumors, spreading to adjacent soft parts, recurred after surgical treatment in two cases. One of them had a lethal course, with pleuro-pulmonary, mediastinal lymph node and hepatic metastases. Histologically, these sarcomas show a malignant mesenchymal component and few benign ameloblastic islands, which often disappear after one or several recurrences. Histoenzymologically, a high level of alkaline phosphatase and ATPase activities is always present, a feature not present in common fibrosarcomas. The ultrastructural study demonstrates, in analogy with odontogenic myxomas, clear cells provided with numerous microfilaments, secretory cells and also some fibroblasts and myofibroblast-like cells. In addition to these pleomorphic cells, a great number of peculiar granular cells with numerous lysosomal bodies were also found. The histogenesis of these tumors in unknown. Perhaps the epithelial component, being unable to assume its functions of organization, may initiate the malignant transformation of its odontogenic mesenchyme.  相似文献   
9.
We present the clinical, radiographical and pathological features of low-grade fibrosarcoma of the left proximal humerus in a 23-year-old man in whom it was necessary to distinguish the tumor from desmoplastic fibroma, malignant fibrous histiocytoma and intramedullary well-differentiated osteosarcoma. The patient presented with a 10-day history of pain in his left upper arm sustained when trying to break his fall with his left hand when slipping in the street. Plain radiography revealed an expanding multilobular osteolytic lesion from the proximal metaphysis to the diaphysis of his left humerus, accompanied by a pathological fracture at the distal portion of the lesion. Open biopsy of the lesion was performed twice; however, a conclusive diagnosis could not be obtained. The patient underwent wide excision and prosthetic replacement of the left proximal humerus. Histologically, the resected tumor was composed of both cellular areas and hypocellular areas. Cellular areas revealed a proliferation of bundles of uniform fibroblastic spindle-shaped cells with minimal cellular atypia, mixed with abundant intercellular collagenization. Mitotic figures were occasionally seen. Hypocellular areas showed myxoid features with loose bundles of collagen fibers. The patient demonstrates no evidence of disease 42 months after surgery. It is important to detect the scant atypical cells for the differential diagnosis of low-grade fibrosarcoma and desmoplastic fibroma of bone.  相似文献   
10.
Translocation 2;11 in a fibroma of tendon sheath   总被引:2,自引:0,他引:2  
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