IRANIAN RED CRESCENT MEDICAL JOURNAL, sa.5, 2021 (SCI-Expanded)
Background: Autologous stem cell transplantation (ASCT) is currently a gold standard treatment for eligible multiple myeloma (MM) patients. The recommended dose of CD34(+) hematopoietic progenitor cells (HPCs) for adequate engraftment is above 2 x 10(6) cells/kg. Objectives: This study aimed to evaluate the relationship between the number of CD34(+) HPCs and the survival in MM patients who underwent ASCT in the Hematology Department of Abdurrahman Yurtaslan Ankara Oncology Training and Research Hospital, Ankara, Turkey. Methods: The statistical population of this consisted of 200 MM patients who underwent ASCT within 2009-2019. The clinical characteristics of the patients, disease status pre-SCT, number of infused CD34(+) cells, neutrophil, and platelet engraftment days were recorded. The patients were divided into two groups, based on whether the re-infused CD34(+) HPCs dose was < 5 x 10(6) cells/kg (Group 1) or >= 5 x 10(6) cells/kg (Group 2). The groups were compared in terms of engraftment and overall survival (OS) times. Results: A total of 200 patients were included in our study. Group 1 (n=125) included patients with < 5 x 10(6) cells/kg CD34(+) HPC reinfusion, and Group 2 (n=75) consisted of patients with = 5 x 10(6) cells/kg CD34(+) HPC re-infusion. The patients' median age scores in Group 1 and Group 2 were 57 (25-71) and 56 (33-72) years, respectively. The median follow-up period was 33 months (6-130). The median OS of all patients was 71 months (95% confidence interval, 59.1-82.9). The median neutrophil and platelet engraftment times were similar between the groups (P=0.4 and P=0.4, respectively). In both groups, the median OS time was 71 months (P=0.8), which was similar. Conclusion: The greater number of CD34(+) HPCs re-infusion for ASCT after high dose melphalan chemotherapy in MM patients did not affect platelet and neutrophil engraftment time and OS; therefore, this amount of reinfusion was not required.