• The Journal of the Korean bone and joint tumor society
• /
• v.1 no.1
• /
• pp.30-37
• /
• 1995

The prognosis of parosteal osteosarcoma is better than any other malignant bone tumors, but there are many controversies in its treatment. We tried to evaluate the prognosis and the effectiveness of limb-salvage operation in the treatment of the parosteal osteosarcoma. We experienced 12 patients of conventional parosteal osteosarcoma(2 males and 10 females) from 1981 to 1991. The limb-salvage operations with wide resection margin were done in 8 patients(5 tumer prosthesis, 2 resection arthrodesis and 1 vascularized fibular transplantation), marginal en-bloc resection and amputation in 2 patients, respectively. The duration of mean follow up was 5 years and 9 months, ranging from 2 year-3 months to 11 years, except of the patient who died with metastasis 1 year 8 months after. The disease-free survival rate(DFSR) of all patients was 68% and that of the patients treated with limb-salvage operation was 88% at 7 years. The DFSR was 33% with marginal margin(3 cases) and 89% with wide margin(9 cases) at 7 years. The results were unsatisfactory in the conventional parosteal osteosarcoma treated with marginal resection. The limb-salvage operation with wide surgical margin was thought to be the treatment of choice.

• The Journal of the Korean bone and joint tumor society
• /
• v.5 no.1
• /
• pp.70-75
• /
• 1999

We present a case of parosteal osteosarcoma of the femur with secondary dedifferentiation. This 57-year-old woman was radiologically diagnosed as a parosteal osteosarcoma in 1987. In 1992, excisional biopsy revealed a classical parosteal osteosarcoma with diploidy DNA pattern. In 1998, she revisited due to a recurrent tumor with pathologic fracture. The resected specimen showed a classic parosteal osteosarcoma with area of dedifferentiation, showing high-grade spindle cell sarcoma. This dedifferentiated area revealed aneuploidy cell population on DNA flow cytometry. This case reminds us that not all parosteal osteosarcomas are low-grade lesions. Some low-grade lesions may dedifferentiate to become high-grade tumors after inadequate excision.

• The Journal of the Korean bone and joint tumor society
• /
• v.4 no.1
• /
• pp.59-64
• /
• 1998

Parosteal osteosarcoma is characterized as a densely ossifying lesion, usually occurring on the surface near the metaphyses of a long bone. The histological pattern is a well- differentiated mature bone trabeculae with a hypocellular spindle-cell stroma. The cytological details are those of a low-grade malignant lesion. The natural history of this lesion is indolent local growth, late invasion of the underlying bone, and infrequently, distant metastasis. However, there is a significant risk of eventual dedifferentiation into a high-grade lesion. We report here-a case of parosteal osteosarcoma dedifferentiated into a high-grade lesion, which occurred in the left distal femur of a 40-years-old woman, and discuss the experience in detail.

• The Journal of the Korean bone and joint tumor society
• /
• v.5 no.1
• /
• pp.82-85
• /
• 1999

A parosteal lipoma is a benign tumor containing mature adipose tissue and is intimately related to the adjacent periosteum. We experienced a very rare case of parosteal lipoma arising from the shaft of femur. A 46 years old lady visited the hospital with complaining of slowly growing mass in her thigh for 7 month. Initially, it was difficult to differentiate from osteochondroma, parosteal osteosarcoma or liposarcoma. Based on the assessment of plain radiogram and magnetic resonance imaging, it was suspected the parosteal lipoma or osteosarcoma. Marginal excision was performed, and it was confirmed to parosteal lipoma histologically. We present the case with review of literatures.

• The Journal of the Korean bone and joint tumor society
• /
• v.13 no.2
• /
• pp.195-200
• /
• 2007

Dedifferentiated parosteal osteosarcoma is an uncommon variant of osteosarcoma. Dedifferentiation is known to be associated with a greater metastatic potential and a more rapid lethal clinical course. Thus recognition of dedifferentiation is important to establish the treatment strategy. But there may be few significant clinical clues to distinguish between dedifferentiated parosteal osteosarcoma and conventional one. A 29-year-old woman presented with 2-year history of discomfort and swelling in her proximal thigh. Examination showed a large, hard, non-mobile mass. Radiographs revealed a large ossified mass attached to the proximal femur. Diagnosis of parosteal osteosarcoma was established by MRI and needle biopsy. But she had a history of abrupt severe thigh pain and increased swelling before surgery. Follow up MRI showed enlargement of mass with invasion to muscle around tumor. The patient underwent an en-bloc resection of tumor and reconstruction. Histological examination showed parosteal sarcoma with dedifferentiation. The patient expired due to local recurrence of tumor and distant lung metastasis 2 months after the surgery. In case with rapid growth of a lesion or unusual severe pain, one must have a high index of suspicion with regard to dedifferentiation.

• Clinics in Shoulder and Elbow
• /
• v.24 no.4
• /
• pp.261-264
• /
• 2021

A large parosteal osteoma arising on the surface of the right clavicle of a 39-year-old male patient was suspected preoperatively as a parosteal osteosarcoma. The lesion was treated with wide resection and allograft reconstruction. In this case report, we discuss the accurate diagnosis and appropriate surgical treatment for unusual clavicular tumors.

• The Journal of the Korean bone and joint tumor society
• /
• v.16 no.2
• /
• pp.95-98
• /
• 2010

Synovial chondromatosis is a benign nodular cartilaginous proliferation arising in the synovium of joints. The radiolographic features of this condition are variable. Rarely, it would be confused with malignancy such as chondrosarcoma, osteosarcoma or synovial sarcoma. We report a case of primary synovial chondromatosis of the posterior aspect of the proximal tibia mimicking a parosteal osteoarcoma on the radiography, which showed a homogeneously radiopaque juxtacortical mass. However, subsequent computed tomography (CT) showed multiple intra-articular masses containing chondroid mineralization, suggesting synovial chondromatosis.

• The Journal of the Korean bone and joint tumor society
• /
• v.5 no.3
• /
• pp.178-182
• /
• 1999

We report a case of bizarre parosteal osteochondromatous proliferation of the right femur in an 18-year-old man. Roentgenograms showed a calcific mass attached to the underlying cortex with a broad base. Histologically, the lesion showed hypercellular cartilaginous tissue with maturation into trabecular bone, which contained spindle cells and lymphocytes in the intertrabecular spaces. Bizarre parosteal osteochondromatous proliferations are a form of heterotopic ossification and should not be mistaken for osteosarcoma or chondrosarcoma.

• The Journal of the Korean bone and joint tumor society
• /
• v.8 no.1
• /
• pp.32-37
• /
• 2002

High grade surface osteosarcoma is the most rare subtype of osteosarcoma arising on the surface of bone, accounting for less than 1% of the total number of osteosarcomas. Only a few case reports and studies have been reported in the world. In Korea, only one case out of 127 osteosarcomas has been described up to now, but there was no information about the patient, clinicopathologic features and treatment. We experienced a case of high grade surface osteosarcoma in the subtrochanteric area of a 66-year-old female and treated her with neoadjuvant chemotheraphy, wide resection and limb salvage operation with tumor prosthesis and adjuvant chemotheraphy. This tumor is identical to conventional high grade intramedullary osteosarcoma in histology, treatment and prognosis. So, this tumor should be differentiated from other surface osteosarcomas such as parosteal osteosarcoma and periosteal osteosarcoma.

• The Journal of the Korean bone and joint tumor society
• /
• v.19 no.1
• /
• pp.20-27
• /
• 2013

Purpose: The purpose of this study was to evaluate the oncologic outcomes of parosteal osteosarcoma (POS) and to ascertain the fates of patients after local recurrence (LR). Materials and Methods: The authors retrospectively reviewed 22 POS patients with an average follow-up of 114 months (range: 36-235 months). Seven of the 22 patients were referred after LR. There were 17 Stage IB and 5 Stage IIB (G2, 2; dedifferentiation, 3). Tumors were located in the femur (11) and in other locations (11). Initial surgical margins were wide in 10, marginal in 5, and intralesional in 7. Correlations between clinico-pathologic variables and LR and clinical courses after LR were evaluated. Results: The 10-year overall survival rate was 85.7%. Three (14%) patients developed distant metastasis and all of them succumbed to the disease. Nine (41%) patients developed LR. Tumor location, resection type, and surgical margin were found to be correlated with LR. At final follow-up, 7 of the 9 patients that experienced local failure achieved no evidence of disease. Conclusion: A substantial risk of misdiagnosis exists, especially for POS in other than a femoral location. Recurrent tumor re-excision is possible in most cases; however, patients with an aggressive recurrence pattern deserve special attention.