tailieunhanh - Chapter 104. Acute and Chronic Myeloid Leukemia (Part 16)

Interferon Before imatinib, when allogeneic SCT was not feasible, IFN-α therapy was the treatment of choice. Only longer follow-up of patients treated with imatinib will prove whether IFN-α will still have a role in the treatment of CML. Its mode(s) of action in CML is still unknown. Chemotherapy Initial management of patients with chemotherapy is currently reserved for rapid lowering of WBCs, reduction of symptoms, and reversal of symptomatic splenomegaly. Hydroxyurea, a ribonucleotide reductase inhibitor, induces rapid disease control. The initial dose is 1–4 g/d; the dose should be halved with each 50% reduction of the leukocyte count. Unfortunately, cytogenetic remissions with. | Chapter 104. Acute and Chronic Myeloid Leukemia Part 16 Interferon Before imatinib when allogeneic SCT was not feasible IFN-a therapy was the treatment of choice. Only longer follow-up of patients treated with imatinib will prove whether IFN-a will still have a role in the treatment of CML. Its mode s of action in CML is still unknown. Chemotherapy Initial management of patients with chemotherapy is currently reserved for rapid lowering of WBCs reduction of symptoms and reversal of symptomatic splenomegaly. Hydroxyurea a ribonucleotide reductase inhibitor induces rapid disease control. The initial dose is 1-4 g d the dose should be halved with each 50 reduction of the leukocyte count. Unfortunately cytogenetic remissions with hydroxyurea are uncommon. Busulphan an alkylating agent that acts on early progenitor cells has a more prolonged effect. However we do not recommend its use because of its serious side effects which include unexpected and occasionally fatal myelosuppression in 5-10 of patients pulmonary endocardial and marrow fibrosis and an Addison-like wasting syndrome. Autologous SCT Autologous SCT could potentially cure CML if a means to select the residual normal progenitors which coexist with their malignant counterparts could be developed. As a source of autologous hematopoietic stem cells for transplantation blood offers certain advantages over marrow . faster engraftment for the patient and no general anesthesia for the donor . Normal hematopoietic stem cells appear with increased frequency in the blood of patients with CML during the recovery phase after chemotherapy and G-CSF. A role for imatinib before stem cell collection to achieve minimal residual disease and following transplantation to maintain this status is currently being investigated. Specifically several groups store peripheral blood stem cells from patients in major or complete molecular remissions. However only a few cases have been transplanted following imatinib therapy. Therefore