Between 1987-1988 we treated, in a cooperative study, 13 patients in blast crisis of CGL according to Koller and Miller's regimen. We observed no return to the chronic phase of the disease, while some patients suffered major drug-induced side effects. Six patients in accelerated phase were treated with the same combination therapy. All of them responded with a return to the chronic phase for a median of 4.5 months. In our hands the combination of plicamycin and hydroxyurea was ineffective in patients with CGL in blast crisis. This regimen could deserve further evaluation in patients with CGL in acceleration.