Initial evaluation of reduced fractionation in the irradiation of malignant epithelial tumors

From July, 1971, through June, 1974, 170 patients underwent radiation therapy with reduced fractionation at the Milwaukee County General Hospital and the Wood Veterans Administration Hospital. One or two fractions per week were delivered for five to seven weeks to a total dose based on the tolerance of normal tissues predicted by the nominal standard dose (NSD) hypothesis of Ellis. Three groups of patients were selected from this heterogeneous population for detailed analysis--carcinomas of the skin, breast, and lung. The 72 patients evaluated provide useful data in regard to acute and subacute reactions. Short term assessment of local tumor control in relation to surrounding normal tissue response is similar to that with conventional fractionation for each of these malignant epithelial tumors.