A. Wieczorkiewicz-Kabut

Very poor outcome of leukemic transformation in myelofibrosis: a single center experience with 13 patients

Myelofi brosis (MF) is a chronic Philadelphia-negative myeloproliferative neoplasm characterized by bone marrow fi brosis, extramedullary hematopoiesis, a leukoerythroblastic blood picture and various degrees of cytopenia [1]. Th e median survival of patients with primary myelofi brosis (PMF) ranges from 3 to 5 years and most patients will fi nally die from bone marrow failure or leukemic transformation (LT) [2]. It has been demonstrated that approximately 20% of patients with MF over a 10-year period will transform to acute leukemia, and the median survival of patients with LT is about 3 months [3]. Th e aim of this study was to evaluate the risk factors, clinical outcome and therapeutic options for patients with LT in MF. A total of 77 patients with PMF ( n 42) and post-polycythemia vera/essential thrombocythemia (PV/ET) MF ( n 35) diagnosed between 1999 and 2010 were included in the study. Th ere were 41 females and 36 males, with a median age of 61 at diagnosis (range 19 – 81 years). All patients gave informed consent and the study was approved by the Local Ethics Committee of Silesian Medical University. Before a patient entered the study, reactive causes of myelofi brosis were carefully excluded. Bone marrow trephine biopsy was performed at diagnosis and the grade of fi brosis was assessed according to the well-known classifi cation [4]. Lille score and international prognostic scoring system (IPSS) score were established at the time of MF diagnosis in all patients [2,5]. Due to the small sample size for LT preceded by PMF, post-PV MF and post-ET MF were grouped together. A diagnosis of LT required peripheral blood or bone marrow blasts to be greater than 20%. Chromosomes were analyzed using the conventional G-banding technique and the JAK2V617F point mutation was detected using a commercially available kit, MutaScreen O (Ipsogen, Marseille, France). Th e survival of patients with LT was defi ned as the interval from the date of diagnosis of LT to either death or last contact. Th e distribution of overall survival and leukemia-free survival was estimated using the method of Kaplan and Meier. Variables describing patient characteristics at diagnosis

Early assessment of donor CD34 + positive cells chimerism after allogeneic stem cell transplantation in acute myeloid leukemia/myelodysplastic syndrome patients – pilot study

Introduction. In high-risk acute myeloid leukaemia/myelodysplastic syndrome patients, relapse remains the major cause of treatment failure after allogeneic stem cell transplantation (alloSCT). The investigation of lineage-specific chimerism has become an important tool in the management of patients during the post-transplant period. Aim. Early assessment of lineage specific chimerism in patients who underwent allogeneic hematopoietic stem cell transplantation. Material and methods. 55 patients with acute myeloid leukemia and myelodysplastic syndrome who underwent alloSCT were included in the study. Flow cytometric analysis and cell sorting was performed in bone marrow collected at day 30 after alloSCT. For the purpose of this study we analyzed sorted immature progenitor cells (CD34+CD19-) using STR method. Results. All patients who relapsed presented with lower donor chimerism in CD34+ positive cells in comparison to the group of patients in remission of the underlying disease. Median value of chimerism in CD34+ positive cells in the group of patients who relapsed was 14.5% (range 0-51%), whereas in patients who remained in remission of the underlying disease, chimerism in CD34+ never fell below 97% (median 100%, range 97-100%). All relapses occurred during the first year after alloSCT. Median time to relapse was 107 days (range 28-323). Conclusions. Early assessment of chimerism in CD34+ cells sorted out of bone marrow is a sensitive technique to detect residual or reoccurring disease after allogeneic SCT. The assessment of donor chimerism in CD34+ cells in day +30 after alloSCT seems to be relevant in post-transplant care of high risk patients.