Finding the Optimal Conditioning Regimen for Relapsed/Refractory Lymphoma Patients Undergoing Autologous Hematopoietic Cell Transplantation: A Retrospective Comparison of BEAM and High-Dose ICE.

OBJECTIVE: High-dose chemotherapy followed by autologous hematopoietic stem cell transplantation (AHCT) is a well-defined treatment modality for relapsed/refractory non-Hodgkin's lymphoma (NHL) and Hodgkin's lymphoma (HL). Although there are several options in terms of conditioning regimens before AHCT, no one treatment is accepted as a standard of care. This study aimed to compare different conditioning regimens for the treatment of NHL and HL. MATERIALS AND METHODS: Medical records of 62 patients who had undergone AHCT following BEAM (BCNU, etoposide, cytarabine, and melphalan) and high-dose ICE (hICE; ifosfamide, carboplatin, and etoposide) conditioning regimens were analyzed retrospectively and compared in terms of efficacy and adverse effects. RESULTS: The study included a total of 29 and 33 patients diagnosed with relapsed/refractory NHL and HL, respectively. Patients received BEAM (n=37) or hICE (n=25) regimens for conditioning. One-year overall survival was 73±6% in all patients. One-year overall survival was 71±8% and 74±9% in the BEAM and hICE groups, respectively (p=0.86). The incidences of nausea/vomiting (grade ≥2) (84% vs. 44.7%; p=0.04) and mucositis (grade ≥2) (13% vs. 3%; p=0.002) were higher in the hICE group compared to the BEAM group. In addition, we witnessed significantly more hepatotoxicity of grade ≥2 (40% vs. 2.7%; p<0.005) and nephrotoxicity of grade ≥2 (48% vs. 2.7%; p<0.005) among patients who received hICE. Significantly more patients (n=4; 25%) in the hICE group experienced veno-occlusive disease (VOD) compared to the BEAM arm, where no patients developed VOD (p=0.01). CONCLUSION: There was no difference in terms of overall survival between the BEAM and hICE groups. We observed significantly more adverse effects among patients treated with hICE. The BEAM regimen seems to be superior to hICE in terms of toxicity profile with comparable efficacy in patients with relapsed/refractory NHL and HL.

Microbial contamination of hematopoietic progenitor cell products.

INTRODUCTION: Microbial screening for contamination is a part of hematopoietic progenitor cell (HPC) collection and infusion procedure. We aimed to find out our microbial contamination rates during collection, processing and infusion steps of HPC products. We also evaluated the clinical course of patients who received contaminated HPC products. PATIENTS-METHODS: We retrospectively analyzed microbial contamination records of HPC grafts between 2010 and 2012. HPC products of autologous donors were evaluated for contamination at three steps: at the end of mobilization, following processing with DMSO and just before stem cell infusion. Grafts of allogeneic donors were assessed only before HPC transplantation (HCT). Microbiological analysis of HPC samples were performed with an automated system (BacT/Alert®). RESULT: During the study period a total of 492 mobilization procedures were performed on 329 (214 autologous and 115 allogeneic) donors. Bacterial contamination has been detected in 103 of 1630 samples (6%). Ninety-seven out of 1162 blood samples (8%) from 265 patients who were treated with HCT were contaminated. Forty-six patients (41 autologous and 5 allogeneic) were transplanted with contaminated HPC products. During HCT 42 patients experienced febrile neutropenic attack and 34 of them had positive blood culture results. In none of these 34 patients the isolated pathogens were the same organisms with those found in the final contaminated stem cell product before stem cell infusion. None of the patients who received contaminated products died because of sepsis within the posttransplant 30days. There was no significant difference between patients who received contaminated and non-contaminated products in terms of the first day of fever, duration of fever, engraftment kinetics and duration of hospitalization. CONCLUSION: Our results suggest that microbial contamination of HPC products is an issue to be prevented, although it may not have a major impact on the general success of HCT.

Which regimen is better for stem cell mobilization of lymphoma patients?

Although chemotherapy combined with G-CSF is an effective method for hematopoietic stem cell mobilization, standard chemotherapy protocol leading to best stem cell yield is not defined. In our study, we aimed to assess the impact of chemotherapy choice on mobilization outcome in lymphoma patients. Patients were mobilized with cyclophosphamide (n:15), ASHAP (n:11) or VGEPP (n:12) protocols. Groups were similar according to collected CD34+ cell count, total nucleated cell count and median apheresis days. Five out of fifteen (33%) patients could not be mobilized in Cy group but there was only one failed mobilization attempt in both salvage groups (9% with ASHAP vs 8% with VGEPP). In conclusion, we showed that VGEPP and ASHAP are safe protocols in terms of stem cell mobilization and have similar mobilization capacity as cyclophosphamide alone.

Predicting the successful peripheral blood stem cell harvesting.

Several previously defined factors affecting the mobilization success include age, prior chemotherapy lines, exposure to myelotoxic agents, extended field radiotherapy and bone marrow infiltration with the primary disease. The purpose of this study was to retrospectively analyze the influence of the predictive factors for a successful peripheral stem cell mobilization. We enrolled a total of 145 patients into the study (non-Hodgkin lymphoma (n: 40), Hodgkin lymphoma (n: 36), myeloma (n: 64), solid tumors (n:5)) who received autologous stem cell transplantation between 2009 and 2012. In multivariate analysis only platelet count was found to be related with mobilization outcome (p<0.05). Knowing predictive factors for successful mobilization may be useful to define the best timing for mobilization and the most appropriate mobilizing agents for proper patient population.