DELAYED ENGRAFTMENT OF 4-HYDROPEROXYCYCLOPHOSPHAMIDE-PURGED AUTOLOGOUS BONE-MARROW AFTER INDUCTION TREATMENT CONTAINING MITOXANTRONE FOR ACUTE MYELOGENOUS LEUKEMIA

We have previously documented that adults with de novo acute myelogous leukemia (AML) who are induced into first complete remission with mit oxantrone and high-dose cytarabine are more likely than those induced with daunorubicin and high-dose cytarabine to develop a bone marrow in jury pattern with delayed cytopenias after achieving initial complete remission, a phenomenon we have termed post-remission cytopenia syndro me. We therefore retrospectively compared the engraftment kinetics of mitoxantrone and daunorubicin patients following 4-hydroperoxycyclopho sphamide (4HC) purged autologous bone marrow transplant (ABMT) with bu sulfan-etoposide conditioning. Despite equivalent graft colony forming units granulocyte macrophage (CFU-GM), mitoxantrone patients (n = 13) took a median 7 weeks longer to achieve 1.0 x 10(9)/l granulocytes, 5 weeks longer to achieve platelet transfusion independence, and 10 wee ks longer to achieve red blood cell transfusion independence, and requ ired more platelet transfusions (P = 0.008), than daunorubicin patient s (n = 13). Patients experiencing the postremission cytopenia syndrome (n = 11) had significantly slower engraftment than those not experien cing the syndrome (n = 15; P less than or equal to 0.04). Two mitoxant rone and five daunorubicin patients have relapsed after ABMT (P = 0.38 ). We conclude that the type of induction chemotherapy used in untreat ed adults with de novo AML can influence subsequent engraftment after 4HC-purged ABMT. We believe that mitoxantrone combined with high-dose cytarabine should be avoided as induction chemotherapy in patients for whom 4HC-purged ABMT is planned.