Extramedullary lesions in non-lymphocytic leukemia: results of radiation therapy.

Fifty-four courses of radiotherapy were given to 33 patients with symptomatic extramedullary involvement by non-lymphocytic leukemia. Among them were 23 cases of granulocytic sarcoma. Analysis of the treatment response showed that age, hematopathologic type and quality of irradiation did not influence the radiation response. However, a dose response relationship could be demonstrated with a statistically significant difference in response among the four groups of patients treated to total doses of less than 1000 rad, 1000-1999 rad, 2000-2999 rad, and greater than or equal to 3000 rad (p = 0.003). We suggest irradiating all extramedullary lesions to at least 1100 ret.