Twenty-one patients with Philadelphia chromosome-positive chronic myelogenous leukemia (CML) in advanced phases were treated with piperazinedione (PIP), total body irradiation (TBI) and allogeneic bone marrow transplantation. Eleven were in blastic transformation, five were in accelerated phase, and five were in second chronic phase. The median age was 29 years (range, 13-41 years); there were 14 males. All patients but one were rendered aplastic by this regimen. Of these, 17 had hematologic engraftment, recovering granulocytes to 1.0 x 10(9)/l in a median of 28 days (range, 11-52 days). Three patients failed to engraft. Of those who engrafted, five relapsed and died of disease, one relapsed and died of a polymicrobial wound infection, nine patients died of treatment-related complications, including graft-versus-host disease, interstitial pneumonitis and sepsis, and one patient developed large-cell lymphoma 27 months after transplant and died of this 18 months later. One patient relapsed after 31 months died of polymicrobial sepsis at 37 months, and one patient remains disease-free at 54+ months. The 3-year survival rate was 14%. Survival at 1 year was related to having a spleen that did not extend beyond 2 cm below the left costal margin at the time of transplantation, and those with a large spleen at initial presentation relapsed more often. PIP-TBI with allogeneic bone marrow transplantation can induce durable remissions in a small proportion of patients in advanced phases of CML, but it is not superior to cyclophosphamide-TBI in this patient group.