Simultaneous occurrence of osteosarcoma and osteochondroma following treatment of neuroblastoma with chemotherapy, radiotherapy, and bone marrow transplantation.

Radiation-induced bone changes and second malignancies, as well as benign tumors, following bone marrow transplantation are being reported with increasing frequency. An osteosarcoma of the fourth right rib and an osteochondroma of the left scapula developed in a long-term survivor of abdominal neuroblastoma treated with chemotherapy, local radiation, and bone marrow transplantation. All these treatment modalities are known to induce neoplasia.