Misonidazole with small dose fractions in an experimental osteosarcoma

The mouse osteosarcoma C22LR was irradiated with a single X-ray dose of 1000 or 1500 rad (to prevent rapid growth) and then with fractionated doses of 300 or 600 rad each. Half the mice were given 0.8 mg/g of misonidazole 1 h before irradiation. Tumour growth delay was determined. The radiosensitizer did enhance the effect of small (300 rad) doses per fraction, as well as that of 600 rad doses.