Treatment of osteosarcoma by interferon and differentiated surgery.

: Since 1972, all cases of osteosarcoma (48 patients) at the Karolinska Hospital in Stockholm have been treated by leukocyte interferon. It has been administered by intra-muscular injections with a dosage of 3 million standard interferon units daily for one month and thereafter 3 times weekly for a further 17 months. Thirty-two patients were subjected to amputation or disarticulation, but in 16 cases local surgery has been resorted to and the defect after tumour resection has been replaced by autogenous bone grafting or endoprostheses. In 5 of 16 locally treated cases, local recurrence occurred and amputation was performed. Four of the patients later on succumbed from metastases. The selection of cases which can be treated by local resection is difficult. In the present series, the rate of survival was 58% after 5 years. Before 1972 (historical group) the survival rate was 14%. The corresponding - 5 - year survival figure for the contemporary group treated without interferon is 33%. Although the 58% survival rate seems to represent an effect of interferon on osteosarcoma, no statistically significant conclusions can be drawn.