1. A Case of osteosarcoma is reported which arose 8 years after synovima of the knee had been locally excised. The patient is a 51-year-old housewife who had received irradiation therapy upon her knee for 30 days post-operatively. Following irradiation, asymptomatic latent period lasted 8 years when mass appeared on the site, which was biopsied and diagnosed as osteosarcoma one year later. 2. This case generally suffices the McKennas criterias for irradiation-induced osteosarcoma, 3. It seems to be worthwhile to keep an eye upon the prognosis of this possible case of irradiation- induced osteosarcoma, which is largely reported to be very grave.
Humans ; Knee ; Middle Aged ; Osteosarcoma ; Prognosis ; Sarcoma, Synovial