Allogeneic Hematopoietic Stem Cell Transplantation for Paroxysmal Nocturnal Hemoglobinuria: Multicenter Analysis by the Polish Adult Leukemia Group.

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is the sole potential cure for paroxysmal nocturnal hemoglobinuria (PNH); however, the data on its utility in PNH are limited. This retrospective analysis of patients with PNH who underwent allo-HSCT in 11 Polish centers between 2002 and 2016 comprised 78 patients with PHN, including 27 with classic PNH (cPNH) and 51 with bone marrow failure-associated PNH (BMF/PNH). The cohort was 59% male, with a median age of 29 years (range, 12 to 65 years). There was a history of thrombosis in 12% and a history of hemolysis in 81%, and 92% required erythrocyte transfusions before undergoing allo-HSCT. No patient received eculizumab, and 26% received immunosuppressive treatment. The median time from diagnosis to allo-HSCT was 12 months (range, 1 to 127 months). Almost all patients (94%) received reduced-toxicity conditioning, 66% with treosulfan. The stem cell source was peripheral blood in 72% and an identical sibling donor in 24%. Engraftment occurred in 96% of the patients. With a median follow-up of 5.1 years in patients with cPNH and 3.2 years in patients with BMF/PNH, 3-year overall survival (OS) was 88.9% in the former and 85.1% in the latter (P = not significant [NS]). The 3-year OS for patients with/without thrombosis was 50%/92% (P = NS) in the cPNH group and 83.3%/85.3% (P = NS) in the BMF/PNH group. The 3-year OS for in the BMF/PNH patients with/without hemolysis was 93.9%/62.9% (hazard ratio, .13; P = .016). No other factors impacted OS. After allo-HSCT, the frequency of the PNH clone was reduced to 0%, <1%, and <2.4% in 48%, 48%, and 4% of cPNH patients and in 84%, 11%, and 5% of BMF/PNH patients, respectively. The frequency of acute graft-versus-host disease (GVHD) grade II-IV was 23%, and the cumulative 1-year incidence of extensive chronic GVHD was 10.8% in the BMF/PNH group and 3.7% in the cPNH group. Allo-HSCT is a valid option for PNH patients, effectively eliminating the PNH clone with satisfactory overall survival and acceptable toxicity. Reduced-toxicity conditioning with treosulfan is effective and safe in patients with cPNH and BMF/PNH.

Increased Efficacy of Stem Cell Chemomobilization with Intermediate-Dose Cytarabine Plus Granulocyte Colony-Stimulating Factor (G-CSF) Compared with G-CSF Alone in Patients with Multiple Myeloma: Results of a Randomized Trial.

Mobilization of hematopoietic stem cells for patients with multiple myeloma (MM) may be done using either steady-state granulocyte colony-stimulating factor (G-CSF) or a combination of chemotherapy with G-CSF. The goal of this randomized, open-label, phase 3 trial was to compare the efficacy of chemomobilization using intermediate-dose cytarabine (ID-AraC) plus G-CSF with G-CSF alone in patients with MM referred for tandem autologous stem cell transplantation (autoSCT). The percentage of patients with stem cell yield of at least 5 × 106 CD34+ cells/kg was the primary endpoint. Ninety patients were enrolled, including 44 assigned to the ID-AraC arm and 46 in the G-CSF arm. The threshold number of CD34+ cells was reached in 43 patients (98%) in the ID-AraC arm and in 32 patients (70%) in the G-CSF arm (P = .0003). The median number of collected CD34+ cells was 20.2 × 106 cells/kg in the ID-AraC arm versus 5.9 × 106 cells/kg in the G-CSF arm (P < .000001). A single apheresis was sufficient to achieve the required number of harvested CD34+ cells in 37 patients (86%) in the ID-AraC arm and in 13 patients (41%) in the G-CSF arm (P = .00008). The times to both neutrophil and platelet recovery after autoSCT were significantly shorter in the patients mobilized with ID-AraC. This study provides the first evidence of the advantage of chemomobilization over G-CSF monotherapy in terms of efficacy. ID-AraC with G-CSF should be the preferred chemomobilization protocol for patients with MM scheduled to undergo tandem autoSCT.

The endogenous erythropoietin in correlation with other erythrocytic parameters in patients with head and neck squamous cell carcinoma treated with platinum-based induction chemotherapy.

Between January 2017 and July 2018 103 patients were included in a prospective study of erythropoietin (EPO) monitoring. The group consisted of 33% patients with oropharynx, 29% with oral cavity, 13% with nasopharynx, 6% with larynx, 6% with hypopharynx, 8% with unknown primary cancer, 4% with nasal cavity, and 1% with salivary gland cancer. Clinic stage: T4 - 50, T3 - 21, T2 - 14, T1 - 10, T0 - 8, and N3 - 19, N2 - 61, N1 - 10, N0 - 13. All patients received from one to four cycles of induction chemotherapy. EPO was measured in blood serum by enzyme-labelled chemiluminescent immunometric assay, using an Immulite 2000XPi analyser before the administration and on day 11 of each chemotherapy cycle. During induction chemotherapy the EPO level was elevated in all patients, which is expressed by means of medians: 10.7 (p = 0.000001) in the middle of cycle 1; 10.9 (p = 0.66) before cycle 2; 14.35 (p = 0.000177) in the middle of cycle 2; 14.95 (p = 0.39) before cycle 3, 17.00 (p = 0.00078) in the middle of cycle 3, and 20.9 after cycle 3 (p = 0.41). The correlation analysis conducted indicates that the administration of one chemotherapy dose results in higher EPO release (two-fold increase in EPO concentration) which intensifies reticulocytes (REC) production but without haemoglobin concentration in reticulocytes (HGB-REC) growth. In consequence, it leads to a decrease in RBC and HGB concentration (29-32 cases). The administration of two and three chemotherapy doses results in the subsequent higher release of EPO, which does not intensify REC production. In consequence, anaemia increases (35 cases).

Comparable safety profile of BeEAM (bendamustine, etoposide, cytarabine, melphalan) and BEAM (carmustine, etoposide, cytarabine, melphalan) as conditioning before autologous haematopoietic cell transplantation.

INTRODUCTION: BEAM (carmustine, etoposide, cytarabine, melphalan) is the most frequently used high-dose chemotherapy regimen for patients with lymphoma referred for autologous haematopoietic cell transplantation (autoHCT). Recently, a novel conditioning protocol containing bendamustine instead of carmustine (BeEAM) has been proposed to potentially increase the efficacy. AIM OF THE STUDY: The aim of this study was to retrospectively compare the safety profile of BEAM and BeEAM based on single-centre experience. MATERIAL AND METHODS: A total of 237 consecutive patients with lymphoma treated with either BEAM (n = 174) or BeEAM (n = 63), between the years 2011 and 2016, were included in the analysis. Clinical characteristics of both groups were comparable. Patients with Hodgkin's lymphoma (HL) constituted 49% of the BEAM group and 40% of the BeEAM group. RESULTS: Median time to neutrophil > 0.5 × 109/l recovery was 10 days in both groups (p = 0.29), while median time to platelet > 50 × 109/l recovery was 13 and 14 days after BEAM and BeEAM, respectively (p = 0.12). The toxicity profile was comparable except for arterial hypertension and severe hypokalaemia, which occurred more frequently after BeEAM compared to BEAM (p = 0.02 and p = 0.004, respectively). The rate of early mortality was 1.7% and 1.6%, respectively. The probabilities of the overall and progression-free survival were comparable for both groups (p = 0.73 and p = 0.55, respectively). CONCLUSIONS: Administration of bendamustine instead of carmustine as part of conditioning does not affect the engraftment or the toxicity profile of the regimen. Therefore, BeEAM may be safely used in patients with lymphoma undergoing autoHCT. Its efficacy requires evaluation in prospective studies.

Increased efficacy of intermediate-dose cytarabine + G-CSF compared to DHAP + G-CSF for stem cell mobilization in patients with lymphoma: an analysis by the polish lymphoma research group.

Salvage regimens, like DHAP (dexamethasone, cytarabine, and cisplatin) are frequently used for stem cell mobilization in lymphoma. The aim of this study was to compare the efficacy of DHAP + G-CSF with intermediate-dose cytarabine (ID-AraC) + G-CSF, recently proposed as an alternative schedule. Consecutive patients with Hodgkin's or non-Hodgkin lymphoma who had received at least 2 lines of chemotherapy, mobilized with either DHAP (n = 51) or ID-AraC (n = 50) + G-CSF were included in the analysis. AraC was administered at the dose of 400 mg/m [1] bid intravenously for 2 days followed by filgrastim starting from day 5. In the AraC group, 96 % of patients collected at least 2 × 10 [2] CD34(+) cells/kg compared to 71 % in the DHAP group (p = 0.0006). The CD34(+) cell yield was 9.3 (0-30.3) × 10 [2]/kg vs. 5.6 (0-24.8) × 10 [2]/kg, respectively (p = 0.006). A single apheresis was sufficient to achieve the threshold number of CD34(+) cells in 82 % of the cases after AraC compared to 45 % after DHAP (p = 0.001). We conclude that stem cell mobilization using ID-AraC is associated with a significantly higher efficacy than DHAP, allowing for collection of the transplant material in almost all patients with lymphoma. Our observation suggests that ID-AraC + G-CSF may be a preferable mobilization regimen in this setting.

Association of circulating regulatory T cell number with the incidence and prognosis of diffuse large B-cell lymphoma.

Regulatory T (Treg) cells are essential for maintaining immune tolerance. High Treg frequencies have been reported in peripheral blood and tissue samples of patients with solid tumors while their role in lymphomas, including diffuse large B-cell lymphoma (DLBCL) has not been clearly established. In this study, we analyzed the circulating Treg numbers in 27 patients with newly diagnosed DLBCL and 17 healthy individuals. Tregs were detected by flow cytometry based on CD4(+) CD25(high) FoxP3(+) phenotype. In addition, the expression of CD45RA, HLA-DR, CD62L, CD39, and CTLA4 was analyzed. The number of circulating Treg cells was lower in patients with DLBCL than in healthy controls: median 23 (range, 4-107)/µL vs. 41 (19-104)/µL (P = 0.04). In particular, the number of Tregs expressing CD45RA (naïve Tregs), HLA-DR (marker of activation), and CD62L (L-selectin) was decreased in the DLBCL group. Lower (below median) number of circulating Tregs was associated with reduced chance of achieving complete remission (29% vs. 69%, P = 0.05) and reduced probability of even-free survival (24% vs. 84% at 1 yr, P = 0.0004), independently on the International Prognostic Index. We conclude that low number of circulating Tregs may be associated with poor prognosis in patients with DLBCL. However, our observations require confirmation in larger patient population.

A faster reconstitution of hematopoiesis after autologous transplantation of hematopoietic cells cryopreserved in 7.5% dimethyl sulfoxide if compared to 10% dimethyl sulfoxide containing medium.

Our previous in vitro studies proved a higher clonogenic potential of peripheral blood progenitor cells cryopreserved in 7.5% dimethyl sulfoxide (Me2SO) than in 10% Me2SO containing medium. Based on this findings 7.5% Me2SO cryopreservation medium was introduced to our protocol and both the hematopoietic recovery and infusion-related toxicity were compared with that obtained with standard 10% Me2SO containing solution. Two cohorts of consecutive patients treated with autologous hematopoietic stem cell transplantation were included in the analysis: 56 patients with PBPCs cryopreserved in 7.5% Me2SO solution and 52 patients who obtained cells cryopreserved in 10% Me2SO. Both study groups did not differ significantly with regard to age, diagnosis, and the number of transplanted CD34(+) cells. The time to leukocyte recovery was shorter for patients in the 7.5% Me2SO treated group than in the 10% one. Reconstitution of platelets and the frequency of adverse events did not differ in both groups. Reduction of Me2SO concentration from 10% to 7.5% in cryoprotective mixture has a beneficial impact on leukocyte recovery. These findings require verification in a prospective, randomized trial.

Tandem autologous hematopoietic cell transplantation with sequential use of total marrow irradiation and high-dose melphalan in multiple myeloma.

The goal of this phase II trial was to evaluate safety and efficacy of a tandem autologous hematopoietic cell transplantation (auto-HCT) using sequentially total marrow irradiation (TMI) at the dose of 12 Gy (4 Gy on days -3, -2, and -1) and melphalan 200 mg/m2 for patients with multiple myeloma (MM). TMI was performed using helical tomotherapy. Additional "boosts" (total 24 Gy) were applied for patients with active lesions as revealed by PET-FDG. Fifty patients with median age 58 years (41-64 years) were included and received tandem auto-HCT. TMI resulted in absolute neutropenia in all patients. Grade 3 infections were reported in 30% patients. Other toxicities were rare. Proportion of patients who achieved at least very good partial response increased from 46% before the first auto-HCT to 82% after tandem transplantation. Complete remission rates changed from 10% to 42%, respectively. The probabilities of overall and progression-free survival at 5 years were 74% and 55%, respectively. No patient died without progression. We conclude that conditioning with TMI ± PET-guided "boosts" represents personalized treatment approach in MM and is characterized by very good toxicity profile. Tandem auto-HCT using TMI in sequence with high-dose melphalan appears safe with encouraging early efficacy.

Reduction of DMSO concentration in cryopreservation mixture from 10% to 7.5% and 5% has no impact on engraftment after autologous peripheral blood stem cell transplantation: results of a prospective, randomized study.

The procedure of autologous peripheral blood stem cell transplantation (autoPBSCT) requires cryopreservation of cells in a mixture containing dimethyl sulfoxide (DMSO). DMSO is necessary to secure cell viability, however, its infusion may be toxic to stem cell recipient. The aim of this study was to prospectively evaluate the impact of DMSO concentration on engraftment after autoPBSCT.One-hundred-fifty patients were randomly assigned to one of three study arms; their leukapheresis products were cryopreserved in 10%, 7.5% or 5% DMSO. The study groups did not differ with regard to the diagnosis (mainly lymphomas and multiple myeloma), age, conditioning regimen, and the number of transplanted hematopoietic stem cells. 143 patients were treated with autoPBSCT. The frequency of adverse effects during and shortly after infusion was the lowest in 5% DMSO arm (p = 0.02 compared to 10% DMSO). 4 patients died due to infection before the engraftment. The median time to leukocyte and neutrophil recovery was 10 days in all study groups (p = 0.36 and p = 0.2). As well, the median day of platelet recovery was the same for all DMSO concentrations and equaled 15 days (p = 0.61).In view of these results, 5% DMSO mixture may be considered a new standard in cryopreservation of hematopoietic stem cells.

Immunological properties of bone marrow microenvironment 1 year after allogeneic hematopoietic stem cell transplantation.

Regeneration of the bone marrow microenvironment after transplantation of allogeneic hematopoietic stem cells is poorly explored. The goal of our study was to investigate this process focusing on immunologic factors: concentrations of selected cytokines, expression of immunosuppressive proteins CD47 and CD274 on hematopoietic stem cells, and frequency of T regulatory lymphocytes (Tregs). Bone marrow samples were collected before transplantation, on the day of transplantation, and at the 1-year follow-up. As a control group, we used bone marrow from healthy donors. Prior to the conditioning, the percentage of Tregs and concentration of interleukin-10 were higher in the bone marrow of patients than in healthy donors. The conditioning regimen resulted in increased concentrations of interferon-γ and expression of CD274 on hematopoietic stem cells. Twenty-eight days after transplantation, level of Tregs, expression of CD47, and concentration of interleukin-10 and latency-associated peptide 1 were increased compared with the period before conditioning. Starting from day 100 after transplantation, the microenvironment tended to normalize; the level of Tregs and concentrations of most cytokines were similar to values in the bone marrow of healthy donors.

[Autologous hematopoietic stem cell transplantation for the treatment of aggressive non-Hodgkin's lymphoma. The experience of Polish lymphoma research group]. / Autologiczna transplantacja komórek hematopoetycznych w leczeniu agresywnych chloniaków nieziarniczych Doswiadczenie Polskiej Grupy Badawczej Chloniaków (PLRG).

We analysed the outcome of 200 patients, aged 38 (13-72) years, with aggressive non-Hodgkin's lymphoma (NHL) treated with high-dose chemotherapy followed by autologous haematopoietic stem cell transplantation (autoHSCT) in ten oncohaematological centres belonging to Polish Lymphoma Research Group (PLRG). The source of stem cells for transplantation was peripheral blood (autoPBSCT, n = 153), bone marrow (autoBMT, n = 40) or both blood and bone marrow (n = 7). The probability of overall survival (OS) and progression-free survival at 10 years was 51% (+/- 7%). The transplant-related mortality rate equalled 7%. In multivariate analysis, the only factor influencing independently the probability of OS was disease status at transplantation (p < 0.00001). The outcome of patients transplanted in first or subsequent complete remission or first partial remission (PR) was significantly better compared with subjects given autoHSCT in PR 2 or those with primary or secondary refractoriness. Regarding histological subtypes, the highest OS rate (87%) was observed for anaplastic large T cell lymphoma. The outcome after autoBMT was better compared with autoPBSCT (OS probability: 67% vs. 43%), although the difference did not reach statistical significance. We conclude that high-dose therapy followed by autoHSCT is an effective option for high-risk aggressive NHL. Remission status is a major factor determining long-term outcome. This should be taken into account when referring patients for autoHSCT.