Unusually long survival after autografting in second partial remission of translocation t(4;11) acute infant leukemia

About 70% of children with acute lymphoblastic leukemia may be cured by conventional chemotherapy. The prognosis is considerably worse in infant leukemia with a translocation t(4;11). We report an infant with a diagnosis of cytochemically undifferentiated acute hybrid leukemia (pre pre B-ALL coexpressing one myelomonocytic marker) and t(4;11). Initial clinical presentation and the course of the disease were typical for t(4;11) acute leukemia. After an early hematologic relapse intensive chemotherapy resulted only in a second partial remission 7 months after initial diagnosis. Subsequent bone marrow transplantation with 16 mg/kg busulfan and 200 mg/kg cyclophosphamide followed by the infusion of autologous purged bone marrow resulted in a continuous second remission which has lasted 46 months so far.