Therapy of acute myelocytic leukemia. Daunomycin contrasted with a combination of cytosine arabinoside and 6-thioguanine.

Twenty-three patients with acute myelocytic leukemia (aml) were treated with daunomycin and the results contrasted to those obtained in a subsequent group of 18 patients treated with cytosine arabinoside (ara-c) and 6-thioguanine (tg). The complete remission (cr) rate with daunomycin was 17 percent (mean duration 10.6 months) and the partial remission (pr) rate 26 percent (mean duration 44 days). Corresponding figures in the ara-c and tg group were: cr rate 44 percent (mean duration 5.8 months) and pr rate 17 percent (mean duration 48 days). There were 12 deaths resulting from daunomycin-induced pancytopenia and in ten of the patients who died persistent leukemia infiltrate was found in antemortem marrow specimens or at autopsy. This contrasts with death of six patients from ara-c and tg-induced pancytopenia, in four of whom residual leukemic infiltrate was not evident. Daunomycin alone is deemed not suitable for induction of remission in aml. The results obtained with ara-c and tg are encouraging and may be improved if the number of infectious deaths associated with drug-induced pancytopenia can be reduced.