High-dose cyclophosphamide for mobilization of circulating stem cells in chronic myeloid leukemia.
Experimental and clinical data suggest that Ph-negative myeloid progenitor cells are present, albeit suppressed, in the bone marrow of chronic myeloid leukemia (CML) patients. These residual Ph-negative cells might, in certain circumstances, regain their proliferative advantage over the leukemic Ph-positive clone. Treating CML patients with intensive chemotherapy might allow the harvest, in the early phase of recovery, of Ph-negative stem cells to be used as graft after myeloablative regimen. In our study, 6 CML patients were admitted to a program of autograft with circulating stem cells (CSC) collected after high-dose (5 or 7 g/m2) cyclophosphamide (HD-CY) mobilization. All were autografted, using busulphan 16 mg/kg and melphalan 60 mg/m2. As graft, 4 patients received CSC only, while 2 patients were also given bone marrow, as their peripheral blood CFU-GM yield was unsatisfactory. Two previously alpha-IFN-responding patients showed a slow hematologic recovery, but achieved a marked and further reduction of their Ph-positive metaphases post-graft. Moreover, in one of them, cytogenetic analyses performed on apheresis product showed a more pronounced reduction of his Ph-positive metaphases, as compared to bone marrow samples, suggesting a potential purging effect of the mobilization procedure.
Tringali
S
S
Department of Hematology and Bone Marrow Transplant Unit, Ospedale Cervello, Palermo, Italy.
Santoro
A
A
Scimé
R
R
Vasta
S
S
Pampinella
M
M
Marino
M A
MA
Majolino
I
I
D000293:Adolescent; D000328:Adult; D001781:Blood Component Removal; D003520:Cyclophosphamide / Q000008:administration & dosage* / Q000494:pharmacology / Q000627:therapeutic use; D005260:Female; D006098:Granulocytes; D018380:Hematopoietic Stem Cell Transplantation; D006412:Hematopoietic Stem Cells / Q000473:pathology*; D006801:Humans; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000097:blood / Q000188:drug therapy*; D007958:Leukocyte Count; D008264:Macrophages; D008297:Male; D009504:Neutrophils
D003520:Cyclophosphamide