A 14 year old girl injured her knee in gym class. Since it still hurt 2 weeks later, her physician examined her. Radiographic study showed a mass destroying her distal femur - your sections are from this mass. Features of malignancy include destruction of and extension through the cortex with invasion into adjacent soft tissue. There is some calcification within the neoplasm.
Tumor is present on one side.
Osteoid to one side. Marked pleomorphism, consistent with malignancy. Lab Manual Questions 1. Identify mitotic figures, neoplastic osteoblasts, osteoid. Compare with residual normal bone.