High doses of cyclophosphamide, etoposide and total body irradiation followed by autologous stem cell transplantation in the management of patients with chronic myelogenous leukemia

Eighteen patients with chronic myelogenous leukemia (CML) in chronic (9 patients) or advanced phases (9 patients) underwent autologous bone marrow transplantation (BMT) with a preparative regimen using high doses of cyclophosphamide, etoposide and total body irradiation (CY-VP16-TBI): cyclophosphamide 60 mg/kg daily on days 1 and 2; VP16 250 mg/m² twice daily on days 1-3 and TBI 1020 cGy in six fractionated doses on days 5-7. Autologous marrow cells were reinfused on day 8. Three of the 8 patients in late chronic phase Philadelphia (Ph) chromosome-positive CML (37%) achieved a cytogenetic response, with Ph suppression to 25%, 29% and 44% Ph-positive metaphases, respectively, and lasting for 11, 1 and 3 months, respectively. The median duration of chronic phase following BMT was 26+ months (range 2-33+ months). One patient with Ph-negative, BCR-rearranged, chronic phase CML had a decrease of the BCR-rearranged band to 10% of pretreatment levels, which persisted for 6 months. None of the 9 patients with advanced CML phases (5 in second chronic, 1 in blastic, 3 in accelerated) achieved meaningful cytogenetic responses. Their median survival was 7 months from the time of BMT. Toxicities were mostly related to myelosuppression, particularly thrombocytopenia. Febrile episodes developed in 16 patients (89%). Treatment-related deaths occurred in 2 patients (11%). In summary, autologous BMT using a TBI-containing regimen had acceptable toxicity. Future investigations will evaluate the additional benefit of purged autologous stem cell transplantation in patients with chronic phase CML.