High grade surface osteosarcoma: a clinicopathologic study of 46 cases.

Area of Science:

• Orthopedic Oncology
• Skeletal Radiology
• Bone Pathology

Background:

• High grade surface osteosarcoma is a rare subtype of surface osteosarcoma, representing 8.9% of cases at the institution.
• This rare condition arises on the bone's surface, distinct from conventional osteosarcoma.
• Understanding its characteristics is crucial for diagnosis and treatment planning.

Purpose of the Study:

• To review and characterize high grade surface osteosarcoma.
• To analyze histologic and radiographic features of this rare osteosarcoma subtype.
• To evaluate prognostic factors and treatment outcomes.

Main Methods:

• Retrospective review of 46 high grade surface osteosarcoma cases.
• Histologic features were analyzed in all 46 cases.
• Radiographic features were reviewed in 29 cases.

Main Results:

• A male predominance was observed, with most patients in their second and third decades.
• Lesions predominantly affected long bones, particularly the femur mid-portion.
• Radiographically, lesions showed dense mineralization; histologic findings were similar to conventional osteosarcoma.
• Five-year survival was 46.1%; marginal excision increased recurrence risk.
• Broders Grade 3 tumors had a better prognosis than Grade 4; chemotherapy response correlated with outcomes.

Conclusions:

• High grade surface osteosarcoma has a prognosis comparable to conventional osteosarcoma.
• This contrasts with the generally better prognosis of more common surface osteosarcomas.
• Wide surgical excision and effective systemic chemotherapy are associated with improved clinical results.