Refractory Acute Lymphocytic Leukemia: Role of Stem Cell Transplantation – pro
Although acute lymphoblastic leukemia is curable in one third of adult patients, results vary greatly on account of different clinical, immunologic, and cytogenetic/genetic characteristics. These data, along with the kinetics of response to early treatment, help establish the individual risk class with considerable accuracy, and support risk-specific treatments that should warrant optimal results with as little as possible nonrelapse mortality. Modern first-line therapy consists of standard- and high-dose chemotherapy (increasingly inspired to pediatric principles), hematopoietic stem-cell transplantation, and new targeted therapy, all integrated with the analysis of prognostic factors and the study of subclinical residual disease for key therapeutic decisions. These changes are improving long-term outcome, which in ongoing studies is expected close to 50% or greater.
When ALL does not respond, the prognosis is grim. What to do is not known. Clofarabine has been approved for this situation in pediatric ALL and various combination treatmetns are being explored. Clolar® (clofarabine) Injection is indicated for the treatment of pediatric patients 1 to 21 years old with relapsed or refractory acute lymphoblastic leukemia after at least two prior regimens. CBMT(Canadian BMT Group) suggests that such pateints should be enrolled into clinical trials. It is generallya ccepted, however, that at the very least, a remission be obtained before an allogeneic transplant is attempted.
Relatively few studies have compared transplantation with chemotherapy in adults with acute lymphoblastic leukemia (ALL). The Italian ALL R-87 study suggested that a small number of patients who experience relapse will survive long-term after allogeneic bone marrow transplantation (BMT).
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nccn. ALL, ALL-7, 2013 and MS-27