Case report 628: Low-grade central osteosarcoma.

In summary, low-grade central osteosarcoma is a clinically recognizable rare subtype of osteosarcoma, representing 1.9% of all osteosarcomas found at the Mayo Clinic. The lesion is locally aggressive but also has the potential for metastasis, particularly after local recurrence.

Chondroblastoma of bone.

Chondroblastomas are unusual benign lesions of bone. They classically occur at the ends of long bones in young persons. The roentgenographic and histologic features are typical.