Maintenance therapy of adult acute nonlymphoblastic leukemia. An argument against the need for central nervous system prophylaxis

The need for prophylactic therapy of the central nervous system in adult acute nonlymphoblastic leukemia has been suggested but not proven. Over a 4‐year period from January 1973, to December 1976, we have maintained 40 patients achieving complete remission on a regimen consisting of monthly courses of Cytosine Arabinoside and 6‐thioguanine. Twenty patients remain in remission with a predicted median remission duration for the entire group of 14.5 months. Thirty‐nine of the patients did not have central nervous system leukemia at diagnosis, and only one of these patients (2.6%) has had remission terminated by central nervous system relapse. At least with this effective maintenance regimen there is little need for central nervous system prophylaxis in adult acute nonlymphoblastic leukemia.