Enhancement of radiation-induced normal tissue damage by a fibrosarcoma.

Normal tissue damage in the legs of mice was enhanced by the presence of a fibrosarcoma (FSa I) in the leg at the time of treatment with single doses of 30 to 70 Gy. Damage was assessed by measuring leg contracture 23 to 365 days after irradiation of 8 mm diameter tumors. Animals with and without tumors were treated with 1.0 mg misonidazole/g body weight 30 min before irradiation to ensure that the tumors did not recur and interfere with the assessment of contracture. The data suggest that in some cases, late damage may be enhanced by destructive effects of the tumor on the tumor bed.