Cytogenetic conversion following allogeneic bone marrow transplantation for advanced chronic myelogenous leukemia.

We performed a pilot study to test the effectiveness of allogeneic bone marrow transplantation in the treatment of chronic myelogenous leukemia. Five patients in the advanced stages of chronic myelogenous leukemia (four in blast crisis, one in accelerated phase) with abnormal chromosomes underwent matched-sibling allogeneic bone marrow transplantation after preparation with busulfan, vincristine, cyclophosphamide, and fractionated total body irradiation. Engraftment and conversion to normal chromosome patterns after transplantation occurred in all five patients. None of the patients reverted to an abnormal chromosome pattern of demonstrated clinical or hematologic evidence of recurrent disease during the course of this study; however, longest survival from transplant was 248 days. Allogeneic bone marrow transplantation can eradicate the abnormal clone even in far advanced chronic myelogenous leukemia and can provide normal hematopoiesis. We suggest that clinical complications of chemotherapeutic toxicity and infection were responsible for the short survival in this group of patients, and that these complications could be decreased by performing transplantation in the chronic phase or early accelerated phase of the disease.