Dedifferentiated parosteal osteosarcoma with giant cell tumor component.

Dedifferentiated parosteal osteosarcoma is characterized histologically by the admixture of low-grade fibroblastic osteosarcoma and a high-grade component typically resembling conventional osteosarcoma or malignant fibrous histiocytoma. We report an unusual distal femoral dedifferentiated parosteal osteosarcoma in which the dedifferentiated component resembled a giant cell tumor of bone. This phenotype is rarely described in the dedifferentiated component of a dedifferentiated parosteal osteosarcoma. The clinical, radiographic, and pathologic features of this unusual tumor are described to further expand the histologic spectrum of dedifferentiated parosteal osteosarcoma.

Duke Scholars

Author Diana Marcella Cardona Pathology