Treatment with daunorubicin-DNA (DNR-DNA) or adriamycin-DNA (ADM-DNA) has been evaluated in acute lymphoblastic leukemia of childhood (ALL), acute nonlymphoblastic leukemia (ANLL) and bronchogenic carcinoma (BC). The Five-year survival rate in 69 children with ALL was 73.7% when ADM-DNA was introduced in the treatment and 38% with DNR-DNA (P = 0.03). A randomization between free DNR and DNR-DNA for remission induction in 26 patients with ANLL has shown that the drugs were of equivalent effectiveness. The one-year survival rate was 66% for the DNR group and 64% for the DNR-DNA group. In 59 patients with BC, a randomized trial between ADM-DNA and cyclophosphamide-vinblastine (CTX-VLB) did not show an advantage in favor of one of these treatments. In anaplastic BC (51 patients), there was no difference in survival rate or remission rate between patients treated with ADM or ADM-DNA. No cardiotoxicity was noted among the patients treated with the complexed drugs. ADM-DNA and DNR-DNA are as effective as the free drugs. Cardiotoxicity appears to be reduced.