HIGH-DOSE ETOPOSIDE, CYCLOPHOSPHAMIDE, AND TOTAL-BODY IRRADIATION WITH ALLOGENEIC BONE-MARROW TRANSPLANTATION FOR PATIENTS WITH ACUTE MYELOID-LEUKEMIA IN UNTREATED FIRST RELAPSE - A STUDY BY THE NORTH-AMERICANMARROW TRANSPLANT GROUP

Relapse is a major cause of treatment failure following allogeneic bon e marrow transplantation (BMT) for acute myeloid leukemia (AML). To re duce the risk of relapse following BMT for patients with hematologic m alignancy, our group developed a novel preparative regimen which combi nes high-dose etoposide with cyclophosphamide and total body irradiati on (VPCyTBI). We now report the outcome of therapy with VPCyTBI follow ed by allogeneic BMT for 40 patients with AML in untreated first relap se. With the exception of increased stomatitis, the toxicity of this r egimen was similar to that reported by others for CyTBI. Forty-four mo nths after transplant the actuarial probabilities of disease-free surv ival (DFS), persistent or recurrent leukemia, and transplant related m ortality were .29, .44, and.47 respectively. DFS was improved (P < .01 ) and risk of persistent or recurrent leukemia reduced (P = .005) amon g patients with significant (grade greater than or equal to 2) acute G VHD. Patients with 30% or more blasts on pre-BMT bone marrow examinati on were not at increased risk for persistent or recurrent leukemia. We conclude that VPCyTBI with allogeneic BMT is effective therapy for AM L in untreated first relapse and that a randomized trial comparing thi s regimen with CyTBI is warranted. (C) 1995 by The American Society of Hematology.