ISSN:1082-9784    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Cytologic diagnosis of bone tumors and tumor-like lesions is emphasized as useful for preoperative diagnosis, with the main advantage of being less burdensome to patients, though there are some restrictions for aspiration of a bone lesion. The cytologic distinction between benign and malignant is basically important. Elucidation of cytologic characteristics should lead to a differential diagnosis in consideration of the clinical and radiographic features in a given case. For the diagnosis of a specific histologic subtype, evaluate the cytologic features of the main cells observed and the presence or absence of intercellular matrix (fibrous, myxoid, osteoid or chondroid) intimately associated with the cells. Because osteoclast-like multinucleated giant cells are often observed in aspiration of many bone tumors and tumor-like lesions, other differential diagnostic points are emphasized.

ISSN:1082-9784    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Distinguishing enchondroma from low-grade central chondrosarcoma depends on interpreting histologic findings in the light of clinical and radiologic features. In the long bones, enchondromas do not grow, whereas low-grade chondrosarcomas grow slowly. The distinction should be made based on answers to the question, “Is the lesion growing?” Serial radiographs are the best way to answer this question. Other clues are present in the clinical, radiographic, and histologic findings. In the short tubular bones of the hands and feet and in Ollier’s disease, enchondromas do grow. Therefore, the threshold for regarding central cartilage lesions in these settings should be higher. Extreme cortical expansion and/or infiltration of soft tissues should be present to diagnose chondrosarcoma.

ISSN:1082-9784    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

The skeleton can be affected by a wide variety of processes including infections, growth and development disturbances, circulatory disorders, metabolic diseases, reactive conditions, and neoplasms. All of these processes can occasionally produce a mass in bone that can clinically, radiographically and pathologically simulate a benign or malignant neoplasm. In this article, we discuss a select group of interesting metabolic and reactive lesions including brown tumor, osteomalacic fracture, hemophilic pseudotumor, reactive mixed mesenchymal pseudotumors of periosteal origin, avulsion injuries of bone, and pubic osteolysis, which are prone to be misinterpreted as neoplasms because of their peculiar clinical and morphologic features.

ISSN:1082-9784    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Low-grade central osteosarcoma (LGCOS) is a rare subtype of osteosarcoma most commonly found in the long bones, with a predilection for the distal femur and proximal tibia. The radiographic features of low-grade central osteosarcoma are variable. Usually there is some evidence of aggressive behavior, but sometimes the findings are subtle or even consistent with a benign lesion. Histologically, LGCOS is a bone-forming tumor with a spindle cell stroma showing minimal cytologic atypia. Consequently, it is often misdiagnosed as a benign fibrous lesion, most commonly fibrous dysplasia. The treatment of choice for low-grade central osteosarcoma is resection with a wide surgical margin. Intralesional surgery is associated with a high incidence of recurrence. Therefore, a mistaken diagnosis of fibrous dysplasia can lead to undertreatment and the potential for metastases from a higher-grade recurrent tumor. At times, the radiographic features of low-grade central osteosarcoma suggest a benign lesion; however, fibrous dysplasia virtually never has a malignant radiographic appearance. The most helpful histologic features for distinguishing these tumors are permeation of pre-existing bone or marrow fat, and subtle cytologic atypia. Because clinicopathologic features overlap with fibrous dysplasia, it is important to assess carefully the clinical, radiographic, and histologic findings before making a diagnosis of low-grade central osteosarcoma.

ISSN:1082-9784    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Osteosarcomas (OS) are now divided into several different varieties according to clinical, radiographic, and histologic features. More specifically, OS of the bone surface have distinct radiographic and histologic aspects. Four varieties of OS arising on the bone surface are known: parosteal OS, periosteal OS, usual high-grade surface OS, and dedifferentiated parosteal OS. This case review focuses on dedifferentiation occurring in parosteal OS. Parosteal OS has a good prognosis after wide resection and does not need chemotherapy. Dedifferentiated parosteal OS has a bad prognosis and wide surgical treatment needs to be associated with chemotherapy. Radiographic and histologic features are extremely important to achieve a correct diagnosis in these two rare OS arising on the surface of the bone, which are characterized by a different biologic behaviour.

ISSN:1082-9784    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

The term “malignant giant cell tumor” has been used traditionally to describe a sarcoma arising from a giant cell tumor. However, the term has led to much confusion resulting in the inclusion of many giant cell rich sarcomas not related to giant cell tumor in the group. The term “malignancy in giant cell tumor” has the advantage of overcoming this problem in semantics. It is defined as a sarcoma arising in association with a well documented giant cell tumor, either synchronously or at the site of a previously documented giant cell tumor.

ISSN:1082-9784    

出版商:OVID    

年代:2001

数据来源: OVID