Intraoperative Radiotherapy and Ceramic Prosthesis Replacement for Osteosarcoma

Abstract

As our principal method for the treatment of osteosarcoma, we have adopted since 1978 a limb-saving procedure by a combination of chemotherapy and intraoperative radiotherapy (IOR); in addition, ceramic prosthesis replacement of the irradiated tumor has been carried out in some cases. We have performed IOR with a large dose of electron beams (50--60 Gray) in 21 patients with osteosarcoma between 1978 and 1984. No local recurrence was observed in the irradiated area. Serial histological examination of ten tumors removed 2--10 months after IOR demonstrated a consistent and marked cytocidal effect on the primary lesion, while IOR exhibited very little complications in the surrounding soft tissues. It was not indicated, however, in lesions of the spine and pelvic girdle, because serious radiation injuries to the spinal cord and internal organs could not be ruled out. The overall cumulative survival rate was 32{%}. Since 1982, when a new regimen of chemotherapy was adopted, the estimated culumative 5-year survival rate of ten patients increased to 60{%}. IOR did not prevent lung metastasis of the osteosarcoma, but it always allowed consistent local control of the tumor with little damage to the soft tissues in the extremities. A tumor prosthesis made of alumina ceramics can be used with satisfactory results for tumors developing in the distal femur, provided its design is based on a careful biomechanical analysis.