Long Term Survival of Patients with Chronic Myelocytic Leukemia after Allogeneic Stem Cell Transplant Using a Reduced Intensity Regimen of Melphanlan, Lomustine and Cyclophosphamide.

Abstract

Introduction: Non-ablative regimens have been shown to be effective and less toxic than traditional ablative regimens, but they usually need close monitoring and skillful manipulates e.g. donor lymphocyte infusions. In the present study, we used a novel reduced intensity regimen with melphanlan, lomustine and cyclophosphamide to treat patients with chronic myelocytic leukemia and made a long term follow-up.Methods: 14 patients with median age of 35(23~52) were treated with MCC regimen(Melphanlan 170 mg/m2/d×1, Lomustine 400 mg/m2/d×1, Cyclophosphamide 60 mg/kg/d×2) and the median follow-up time is 6 years; another 16 patients with median age of 33(16~44) were treated with BuCy regimen(Busulfan 4 mg/kg/d×4, Cyclophosphamide 60 mg/kg/d×2) and the median follow-up time is 4 years.Results: All the patients were engrafted successfully and the platelet recovery to 20×109/L was earlier at median 3 days in patients with MCC regimen. 4 of 10 patients examined in MCC group showed mixed chimerism at day 100 post transplant, whereas only 1 of 12 patients examined in BuCy group showed mixed chimerism. All the patients became complete donor sources later without any DLI. The regimen related toxicity was relatively lower in MCC group, especially the incidence and severity of mucositis and liver dysfunction were decreased significantly. The median duration of hospitalization was 39 days (25~55)for patients with MCC regimen, and 55 days (39~90) for BuCy regimen. The 5 year disease-free survival was 71.4% for MCC group and 62.5% for BuCy group, respectively. The transplant related mortality and relapse rate were 21% and 7% for MCC regimen, whereas 25% and 12% for BuCy regimen.Conclusions: MCC regimen is an effective and less toxic conditioning regimen and the long term disease-free survival is as the same as that of BuCy regimen. Considering the cost-effect efficacy, MCC regimen may have some prominent advantages over BuCy regimen. [Display omitted]