Clinical significance of bone morphogenetic activity in osteosarcoma. A study of 20 cases.

Bone morphogenetic activity of osteosarcomas from 20 patients was assayed. The activity was demonstrated as ectopic bone formation on implantation of a lyophilized fraction of the tumor into athymic nude mice in 8 of 20 cases. Osteosarcomas producing bone morphogenetic protein (BMP) differed in clinical features from those not producing BMP. They were characterized radiologically by perpendicular spicules, histologically by osteoblastic type cells, and clinically by an increased serum alkaline phosphatase level, relative resistance to preoperative chemotherapy with Adriamycin (doxorubicin) plus high-dose methotrexate, and a tendency to metastasize to other bones and the lungs.