The management of extramedullary disease in acute leukemia with therapeutic radiations

The authors reviewed 181 patients who received local radiation therapy for the prevention or control of extramedullary disease resulting from acute leukemia. 126 had acute lymphocytic leukemia and 55 had acute granulocytic leukemia. They were treated over a 18-year period of time with different forms of chemotherapy. Most had not received prophylactic CNS radiation therapy. Patients were evaluated for local control until death or hematologic relapse intervened. More than 80% of patients with clinical ALL meningeal leukemia had a successful response to doses over 1000 rads. This same response was not apparent in AML. More than 80% of clinical non-CNS extra medullary leukemia was controlled with doses of 600 rads or greater. Only one patient with extra-medullary relapse is still alive. The authors feel that lower preventative doses of radiation to the CNS are compatible with similar control rates, based on their own data and other suggestive data.