Gemtuzumab Ozogamicin and Stem Cell Mobilization for Autologous Stem Cell Transplantation in Favorable Risk Acute Myeloid Leukemia.

Gemtuzumab ozogamicin (GO), a CD33-targeting antibody drug conjugate, previously showed longer relapse-free survival when combined with induction chemotherapy in patients with favorable-risk acute myeloid leukemia (AML). In this patient population, characterized by lower relapse risk as compared to other ELN risk groups, autologous stem cell transplantation (ASCT) can be used as consolidation strategy. However, there are limited data on the impact of GO on the peripheral blood stem cell (PBSC) mobilization potential. We therefore retrospectively analyzed data from 54 AML patients with favorable-risk AML treated with (n = 17) or without (n = 37) GO during induction treatment. We observed no significant differences in the PBSC mobilization rate between patients treated with vs. without GO. The mobilization success in a first attempt directly following cycle 2 was 65% vs. 70% (p = 0.92); and the mobilization success in a subsequent second attempt after hematologic recovery and repeated stimulation procedure was 24% vs. 19% (p = 0.56). No significant impact on treatment outcome in terms of EFS (p = 0.31) or OS (p = 0.99) was observed. Thus, our results suggest that the addition of GO to induction regimens does not negatively impact PBSC mobilization in favorable-risk AML patients. To our best knowledge, this is the first study comparing the stem cell mobilization potential in favorable-risk AML patients treated with vs. without GO.

Stem cell collection and hematological recovery in the Fondazione Italiana Linfomi (FIL) MCL0208 clinical trial.

In the frontline high-dose phase 3 FIL-MCL0208 trial (NCT02354313), 8% of enrolled mantle cell lymphoma (MCL) patients could not be randomised to receive lenalidomide (LEN) maintenance vs observation after autologous stem cell transplantation (ASCT) due to inadequate hematological recovery and 52% of those who started LEN, needed a dose reduction due to toxicity. We therefore focused on the role played by CD34 + hematopoietic stem cells (PBSC) harvesting and reinfusion on toxicity and outcome. Overall, 90% (n = 245) of enrolled patients who underwent the first leukapheresis collected ≥ 4 × 106 PBSC/kg, 2.6% (n = 7) mobilized < 4 × 106 PBSC/kg and 7.7% (n = 21) failed the collection. Similar results were obtained for the planned second leukapheresis, with only one patient failing both attempts. Median count of reinfused PBSC was 5 × 106/kg and median time to recovery from neutropenia G4 was 10 days from ASCT. No impact of mobilizing subtype or number of reinfused PBSC on hematological recovery and LEN dose reduction was noted. At a median follow-up of 75 months from ASCT, PFS and OS of transplanted patients were 50% and 73%, respectively. A long lasting G4 neutropenia after ASCT (> 10 days) was associated with a worse outcome, both in terms of PFS and OS. In conclusion, although the harvesting procedures proved feasible for younger MCL patients, long-lasting cytopenia following ASCT remains a significant issue: this can hinder the administration of effective maintenance therapies, potentially increasing the relapse rate and negatively affecting survival outcomes.

Evaluation of blood cell count using an automatic hematology analyzer to optimize collection of peripheral blood progenitor cells by leukapheresis.

BACKGROUND: Autologous stem cell transplantation is a treatment modality for several diseases. Prediction of successful mobilization may be useful to optimize hematopoietic stem cell collection. STUDY DESIGN AND METHODS: This was a retrospective study with data from transplantation candidates between September 2015 and December 2021 being analyzed. The medical record of each patient was reviewed to mine mobilization information. The laboratory data analyzed were CD34+ cell enumeration and pre-collection peripheral blood cell count. The primary outcome, good mobilization, was defined as a CD34+ cell count ≥20/µL. RESULTS: This study included 807 patients. Increased patient weight, low mean corpuscular volume, high nucleated red blood cells, peripheral blood mononuclear cell and immature granulocyte counts were significantly associated with good mobilization. In addition, patients diagnosed with multiple myeloma were two times more likely to be good mobilizers than patients with lymphoma. The model was applied to a validation set to identify patients who underwent apheresis (CD34+ cell count ≥10 µL), resulting in a sensitivity of 69 %, a specificity of 95 %, positive predictive value of 98 %, and a negative predictive value of 50 %. CONCLUSION: Success in mobilization was greater in patients who underwent the first mobilization cycle and who had a diagnosis of multiple myeloma. Furthermore, higher body weight, and nucleated red blood cells, immature granulocytes and mononuclear cell counts, as well as low mean corpuscular volumes, were associated with successful mobilization.

Comparison of two autologous hematopoietic stem cell mobilization strategies in patients with multiple myeloma: CE plus G-CSF versus G-CSF only: A single-center retrospective analysis.

BACKGROUND: Despite recent advances in the treatment of multiple myeloma, high-dose chemotherapy followed by autologous hematopoietic stem cell transplantation (ASCT) remains an essential therapeutic keystone. As for the stem cell mobilization procedure, different regimens have been established, usually consisting of a cycle of chemotherapy followed by application of granulocyte-colony stimulating factor (G-CSF), although febrile neutropenia is a common complication. Following national guidelines, our institution decided to primarily use G-CSF only mobilization during the COVID-19 pandemic to minimize the patients' risk of infection and to reduce the burden on the health system. STUDY DESIGN AND METHODS: In this retrospective single-center analysis, the efficacy and safety of G-CSF only mobilization was evaluated and compared to a historic control cohort undergoing chemotherapy-based mobilization by cyclophosphamide and etoposide (CE) plus G-CSF. RESULTS: Although G-CSF only was associated with a higher need for plerixafor administration (p < .0001) and a higher number of apheresis sessions per patient (p = .0002), we were able to collect the target dose of hematopoietic stem cells in the majority of our patients. CE mobilization achieved higher hematopoietic stem cell yields (p = .0015) and shorter apheresis sessions (p < .0001) yet was accompanied by an increased risk of febrile neutropenia (p < .0001). There was no difference in engraftment after ASCT. DISCUSSION: G-CSF only mobilization is a useful option in selected patients with comorbidities and an increased risk of serious infections, especially in the wintertime or in future pandemics.

Vascular access for autologous peripheral blood stem cells collection by large volume leukapheresis: Single center experience.

INTRODUCTION: Peripheral blood stem cell (PBSC) harvesting requires reliable and safe vascular access. In our institution, a change of practice was implemented and the central venous catheter (CVC) placement for all autologous PBSC collections was abandoned in favor of a careful evaluation of peripheral venous access (PVA) for each individual patient. The aim of this prospective study was to evaluate the rate of patients with adequate peripheral veins for autologous PBSC collection and compare patient characteristics, collection efficacy, and complication rate between patients with PVA and CVC. METHOD: Peripheral veins were assessed by the apheresis nurse team in all patients referred between January 2020 and July 2021 to autologous PBSC collection. Only in case of difficult venous access, CVC was inserted. Large volume leukapheresis (LVL) procedures, which processed ≥3 total blood volumes, were performed. RESULTS: In 65 (57%) patients PVA was used, while 49 (43%) patients required placement of short-term CVC. Peripheral venous access was successfully used significantly more often in males (69.8%) (P = 0.010), and patients with multiple myeloma (71.0%) than in patients with non-Hodgkin's lymphoma (35.9%) and Hodgkin's lymphoma patients (33.3%) (P < 0.001). There was a significant difference in the type of prior administered chemotherapy; in the patients who received cytostatics free chemotherapy, PVA was used more often (75.0%) (P = 0.007). In terms of the efficacy and safety of LVLs, there were no differences between procedures performed using PVA and CVCs. CONCLUSION: Peripheral venous access is feasible for autologous PBSC collection in more than a half of patients, in particular in those with multiple myeloma. Changes in the treatment of multiple myeloma, using new proteasome inhibitors-based and immunomodulatory agents that do not adversely affect peripheral veins, have enabled the use of PVA even at the high blood flow rates required by LVL. Peripheral venous access is not associated with safety issues or with a lesser collection efficiency, and it is cost-effective as well. Each patient referred to autologous PBSC collection needs to be evaluated individually by the experienced apheresis team for the most appropriate venous access.

GVHD relapse-free survival after peripheral blood hematopoietic cell transplantation for hematologic malignancies.

The preferred choice for hematopoietic cell transplantation (HCT) donors in India is a matched related donor (MRD) followed by a haploidentical (haplo) donor for patients with hematological malignancies. International data in the haplo-HCT setting is mainly using bone marrow as a source. Almost all HCTs in India use peripheral blood stem cells (PBSC), which increases the risk of graft-versus-host disease (GVHD). In this single-center prospective study from 2017 to 2021, we sought to compare these outcomes prospectively in adult patients with hematological malignancies. Patient, disease, donor, and HCT details were prospectively recorded. GVHD prophylaxis included cyclosporine + methotrexate in MRD-HCT and post-transplant cyclophosphamide (PTCy) based in haplo-HCT. The primary endpoint GVHD relapse-free survival (GRFS) was defined as the time post-HCT without any of the following events: grade III-IV acute GVHD, chronic GVHD requiring systemic immunosuppressive treatment, disease relapse, or death from any cause. A total of 41 MRD and 33 haplo-HCT recipients were included in the study. Both cohorts were matched for age, sex, diagnosis, disease risk index, donor age, sex and CMV mismatches, and CD34 counts. A lower proportion of MRD-HCT recipients than haplo-HCT received myeloablative conditioning (39% vs. 76%, p = 0.002). There was no difference in the cumulative incidence of grade III-IV acute GVHD (16% vs. 27%, p = 0.2) or moderate-to-severe chronic GVHD (58% vs. 71%, p = 0.5). The one-year GRFS was not significantly different (53% vs. 38%, p = 0.2), with median GRFS of 420 and 274 days. The relapse incidence (22% vs. 19%, p = 0.6) and non-relapse mortality (25% vs. 35%, p = 0.4) did not differ. There was no difference in overall survival at one year (60% vs. 52%, p = 0.3). Despite a higher proportion of myeloablative conditioning in the haplo-HCT cohort, all outcomes, including GRFS, were comparable to those of the MRD-HCT cohort. This should encourage patients without an MRD to undergo haplo-HCT.

Splenic irradiation prior to allogeneic transplant conditioning in myelofibrosis: A pilot experience.

INTRODUCTION: In the era of JAK inhibitors, allogeneic stem cell transplantation (HSCT) remains the only curative treatment for patients with Myelofibrosis (MF). Splenic irradiation (SI) may be used to reduce spleen size and related symptoms. METHODS: We conducted a retrospective analysis on 14 patients with MF who underwent HSCT with SI from any donor source at our center between June 2016 and March 2021. All patients received a conditioning backbone based on treosulfan and fludarabine, with post-transplant cyclophosphamide (PTCy) and sirolimus as graft-versus-host disease (GvHD) prophylaxis. Patients received SI with 10 Gy involved-field radiotherapy in five 2-Gy fractions over the course of a week prior to the beginning of conditioning. RESULTS: At transplant all patients were transfusion-dependent and had splenomegaly (median bipolar diameter by ultrasound: 20.75 cm). Overall, 12 patients had received ruxolitinib prior to transplant. Re-evaluation of spleen dimensions was available for 13 patients: median splenic bipolar diameter after at least 3 months from transplant decreased by a median of 25%. With a median post-transplant follow-up of 25 months, 6 patients remain in CR with full-donor chimerism, 3 patients died due to NRM. Overall, 4 patients relapsed. At last follow-up, nine patients are currently alive and achieved transfusion-independence. CONCLUSIONS: In a small cohort of mostly ruxolitinib pre-treated patients, SI and treosulfan-based conditioning appeared a safe and effective tool to reduce spleen dimensions and ameliorate symptoms. Future prospective studies with adequate sample size are warranted to further investigate the usefulness and safety of this approach in MF.

The Impact of Graft CD3+ T-Cell Dose on the Outcome of T-Cell Replete Human Leukocyte Antigen-Mismatched Allogeneic Hematopoietic Peripheral Blood Stem Cells Transplantation.

Background: Data on whether the graft CD3-positive (CD3+) T-cell dose in T-cell-replete human leukocyte antigen (HLA)-mismatched allogeneic hematopoietic peripheral blood stem cells transplantation (PBSCT) influences post-transplant outcomes are controversial. Methods: Using King Hussein Cancer Center (KHCC) Blood and Marrow Transplantation (BMT) Registry database, 52 adult subjects, receiving the first T-cell-replete HLA-mismatched allogeneic hematopoietic PBSCT for acute leukemias or myelodysplastic syndrome, were identified, from January 2017 to December 2020. The cutoff value of graft CD3+ T-cell dose was identified using the receiver operating characteristic (ROC) formula and Youden's analysis. Subjects were divided into two cohorts: cohort 1 with low CD3+ T-cell dose (n = 34) and cohort 2 with high CD3+ T-cell dose (n = 18). Correlative analyses were performed between CD3+ T-cell dose and the risk of graft-versus-host disease (GvHD), relapse, relapse-free survival (RFS), and overall survival (OS). P-values were two-sided and considered significant when P < 0.05. Results: Subject covariates were displayed. Subject's characteristics were comparable, except for higher nucleated cells and more female donors in the high CD3+ T-cell cohort. The 100-day cumulative incidence of acute GvHD (aGvHD) was 45±7% and 3-year cumulative incidence of chronic GvHD (cGvHD) was 28±6.7%. There was no statistically significant difference between the two cohorts in aGvHD (50% vs. 39%, P = 0.4) or cGvHD (29% vs. 22%, P = 0.7). The 2-year cumulative incidence of relapse (CIR) was 67.5±16.3% for low compared with 14.3±6.8% for high CD3+ T-cell cohort (P = 0.018). Fifteen subjects relapsed and 24 have died, 13 due to disease relapse. There was an improvement in 2-year RFS (94% vs. 83%; P = 0.0022) and 2-year OS (91% vs. 89%; P = 0.025) in low CD3+ T-cell cohort compared with high CD3+ T-cell cohort. Graft CD3+ T-cell dose is the only significant risk factor for relapse (P = 002), and OS (P = 0.030) in univariate analysis which was maintained in multivariate for relapse (P = 0.003), but not for OS (P = 0.050). Conclusions: Our data suggest that high graft CD3+ T-cell dose is associated with lower risk of relapse, and might improve long-term survival, but has no influence on the risk of developing aGvHD or cGvHD.

Severe short-term adverse events in related bone marrow or peripheral blood stem cell donors.

The incidence of severe adverse events (SAEs) and associated risk factors in hematopoietic cell transplantation donors needs to be clarified for related donors (relatives of the transplant recipient), whose criteria for donation are more lenient than for unrelated donors. Data from related donors registered in the Japanese national data registry database between 2005 and 2021 were evaluated to determine the association of short-term SAE incidence with donor characteristics at registration.Fourteen of 4339 bone marrow (BM) donors (0.32%) and 54 of 10,684 peripheral blood stem cell (PBSC) donors (0.51%) experienced confirmed SAEs during the short donation period. No deaths were observed. Past medical history was a common risk factor for SAEs in both BM and PBSC donors. Age of 60 years or older and female sex were identified as risk factors for SAEs in PBSC donors. Female sex was also a risk factor for poor mobilization, which resulted in discontinuation of PBSC collection.Although donors should be selected carefully, a certain level of safety is ensured for related donors in Japan. Donor safety should be further increased by improving the selection method for related donors and extending the follow-up period.

Minimal residual disease detected by droplet digital PCR in peripheral blood stem cell grafts has a prognostic impact on high-risk neuroblastoma patients.

More than half of high-risk neuroblastoma (NB) patients have experienced relapse due to the activation of chemoresistant minimal residual disease (MRD) even though they are treated by high-dose chemotherapy with autologous peripheral blood stem cell (PBSC) transplantation. Although MRD in high-risk NB patients can be evaluated by quantitative PCR with several sets of neuroblastoma-associated mRNAs (NB-mRNAs), the prognostic significance of MRD in PBSC grafts (PBSC-MRD) is unclear. In the present study, we collected 20 PBSC grafts from 20 high-risk NB patients and evaluated PBSC-MRD detected by droplet digital PCR (ddPCR) with 7NB-mRNAs (CRMP1, DBH, DDC, GAP43, ISL1, PHOX2B, and TH mRNA). PBSC-MRD in 11 relapsed patients was significantly higher than that in 9 non-relapsed patients. Patients with a higher PBSC-MRD had a lower 3-year event-free survival (P = 0.0148). The present study suggests that PBSC-MRD detected by ddPCR with 7NB-mRNAs has a prognostic impact on high-risk NB patients.

Non-cryopreserved peripheral blood stem cells as a safe and effective alternative for autologous transplantation in multiple myeloma.

BACKGROUND: Autologous stem cell transplantation is the standard procedure for multiple myeloma and the grafts are usually cryopreserved. Previous studies reported advantages in the use of fresh peripheral blood stem cells (PBSC) autotransplantation compared to cryopreservation of the grafts. This study compared the transplant-related outcomes of two graft preservation methods: fresh storage (4°C/72 h) and cryopreservation (-80°C). STUDY DESIGN AND METHODS: We performed an analysis of 45 patients with multiple myeloma under autotransplantation (17 fresh and 28 cryopreserved) from 2017 to 2021. Fresh PBSC were maintained in the refrigerator for three days in a concentration up to 300 × 103 TNC/µL. Cryopreserved PBSC were concentrated by plasma reduction after centrifugation (950 g/10 min/4°C) and an equal volume of cryoprotection solution was added for a final concentration of 300 × 103 TNC/µL, 5% DMSO, 6% hydroxyethyl starch, and 3% human albumin. RESULTS: Neutrophil engraftment was significantly faster with fresh PBSCs (10 vs. 11.5 days, p = 0.045). Adverse effects were more common in cryopreserved PBSC transplantation (75% vs. 35.3% patients; p = 0.013). Post transplantation hospital stay was 20 and 22 days for fresh and cryopreserved PBSCs respectively (p = 0.091). There was no difference in platelet engraftment time (10.5 days for both; p = 0.133), number of antibiotics used after transplantation (3 for fresh and 2.5 for cryopreserved; p = 0.828), days of antibiotic use after transplantation (12.2 days for fresh and 13.3 days for cryopreserved, p = 0.579), and overall survival (p = 0.736). CONCLUSION: The infusion of fresh PBSC refrigerated for up to three days is effective and safe for autologous transplantation in patients with multiple myeloma, which is a useful alternative to cryopreserved PBSC.

Successful Mobilization of Autologous Hematopoietic Peripheral Blood Stem Cells after Salvage Chemotherapy in Patients with Low CD34 Blood Cell Counts.

A major barrier for proceeding to autologous stem cell transplantation (ASCT) is an inability to mobilize and collect an adequate number of peripheral blood (PB) stem cells (PBSC) for the transplant graft. Plerixafor added to granulocyte colony stimulating factor (G-CSF) alone, without prior chemotherapy, significantly improves the mobilization of autologous PBSC in patients with non-Hodgkin lymphoma (NHL) and multiple myeloma (MM). However, the efficacy of plerixafor and the best timing to give the drug to poorly mobilizing patients with very low PB CD34+ cell counts after salvage chemotherapy and G-CSF are not well defined. We hypothesized that PBSC mobilization and collection might be improved in heavily treated patients who mobilized very poorly after salvage chemotherapy and G-CSF by alternating the days of plerixafor administration and leukapheresis. A day of rest between plerixafor doses, while continuing G-CSF, could allow time for some replenishment of the marrow stem/progenitor cell pool before the next mobilization. A retrospective review of collection results in poorly mobilizing patients at our center was undertaken. Three cohorts were identified: those who got every-other-day plerixafor and leukapheresis, those who got sequential plerixafor and leukapheresis and those who got risk adapted plerixafor. Overall, 69% of patients with NHL and MM with PB CD34+ cell counts <5/µL after salvage chemotherapy and G-CSF were ultimately able to collect adequate CD34+ cells to support ASCT using daily plerixafor and leukapheresis. On the alternating plerixafor and leukapheresis schedule, all 17 patients achieved the cumulative CD34+ cell product goals required for ASCT. This positive observation after salvage chemotherapy and G-CSF led to the incorporation at our center of an alternate-day schedule of plerixafor and leukapheresis into our real-time risk adapted strategy for poor mobilizers. © 2023 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

Novel Use of Intraarticular Granulocyte Colony Stimulating Factor (hG-CSF) Combined with Activated Autologous Peripheral Blood Stem Cells Mobilized with Systemic hG-CSF: Safe and Efficient in Early Osteoarthritis.

Osteoarthritis (OA) tends to occur in older individuals frequently burdened with comorbidities and diverse pharmacological interactions. As articular cartilage has low regenerative power, potent local tissue engineering approaches are needed to support chondrogenic differentiation. Acellular preparation methods as well as approaches to coax endogenous reparative cells into the joint space appear to have limited success. Supported by our in-vitro and clinical studies, we propose that our novel intra-articular administration of human granulocyte colony stimulating factor (IA-hG-CSF) combined with autologous activated peripheral blood stem cells (AAPBSC) is safe and offers treatment advantages not seen with other cellular interventions in early osteoarthritis.

Prophylactic Peripheral Blood Stem Cell Collection in Patients with Extensive Bone-Marrow Infiltration of Neuroendocrine Tumours Prior to Peptide Receptor Radionuclide Therapy with 177Lu-DOTATATE.

Peptide receptor radionuclide therapy (PRRT) of metastatic neuroendocrine tumors (NET) can be successfully repeated but may eventually be dose-limited. Since 177Lu-DOTATATE dose limitation may come from hematological rather than renal function, hematological peripheral blood stem cell backup might be desirable. Here, we report our initial experience of peripheral blood stem-cell collection (PBSC) in patients with treatment-related cytopenia and therefore high risk of bone-marrow failure. Five patients with diffuse bone-marrow infiltration of NET and relevant myelosuppression (≥grade 2) received PBSC before one PRRT cycle with 177Lu-DOTATATE (7.6 ± 0.8 GBq/cycle). Standard stem-cell mobilization with Granulocyte-colony stimulating factor (G-CSF) was applied, and successful PBSC was defined as a collection of >2 × 106/kg CD34+ cells. In case of initial failure, Plerixafor was administered in addition to G-CSF prior to apheresis. PBSC was successfully performed in all patients with no adverse events. Median cumulative activity was 44.8 GBq (range, 21.3-62.4). Three patients had been previously treated with PRRT, two of which needed the addition of Plerixafor for stem-cell mobilization. Only one of five patients required autologous peripheral blood stem-cell transplantation during the median follow up time of 28 months. PBSC collection seems to be feasible in NET with bone-marrow involvement and might be worth considering as a backup strategy prior to PRRT, in order to overcome dose-limiting bone-marrow toxicity.

Meloxicam with Filgrastim may Reduce Oxidative Stress in Hematopoietic Progenitor Cells during Mobilization of Autologous Peripheral Blood Stem Cells in Patients with Multiple Myeloma.

Autologous stem cell transplantation (ASCT) is a potentially curative therapy but requires collection of sufficient blood stem cells (PBSC). Up to 40 % of patients with multiple myeloma (MM) fail to collect an optimum number of PBSC using filgrastim only and often require costly plerixafor rescue. The nonsteroidal anti-inflammatory drug meloxicam mobilizes PBSC in mice, nonhuman primates and normal volunteers, and has the potential to attenuate mobilization-induced oxidative stress on stem cells. In a single-center study, we evaluated whether a meloxicam regimen prior to filgrastim increases collection and/or homeostasis of CD34+ cells in MM patients undergoing ASCT. Mobilization was not significantly different with meloxicam in this study; a median of 2.4 × 106 CD34+ cells/kg were collected in the first apheresis and 9.2 × 106 CD34+ cells/kg were collected overall for patients mobilized with meloxicam-filgrastim, versus 4.1 × 106 in first apheresis and 7.2 × 106/kg overall for patients mobilized with filgrastim alone. CXCR4 expression was reduced on CD34+ cells and a higher CD4+/CD8+ T-cell ratio was observed after mobilization with meloxicam-filgrastim. All patients treated with meloxicam-filgrastim underwent ASCT, with neutrophil and platelet engraftment similar to filgrastim alone. RNA sequencing of purified CD34+ cells from 22 MM patients mobilized with meloxicam-filgrastim and 10 patients mobilized with filgrastim only identified > 4,800 differentially expressed genes (FDR < 0.05). Enrichment analysis indicated significant attenuation of oxidative phosphorylation and translational activity, possibly mediated by SIRT1, suggesting meloxicam may counteract oxidative stress during PBSC collection. Our results indicate that meloxicam was a safe, low-cost supplement to filgrastim mobilization, which appeared to mitigate HSPC oxidative stress, and may represent a simple means to lessen stem cell exhaustion and enhance graft quality.

Local Radiation Therapy Before and During Induction Delays Stem Cell Mobilization and Collection in Multiple Myeloma Patients.

In multiple myeloma, local radiation therapy (RT) of osseous lesions before peripheral blood stem cell (PBSC) mobilization is assumed to impair the PBSC mobilization and collection. However, the results of previously published studies are inconsistent and do not evaluate detailed metrics of RT and PBSC outcome parameters. In total, 352 patients undergoing PBSC mobilizations and RT in first-line treatment were evaluated. Patients were grouped into RT (n = 283) and no RT (n = 69) before PBSC mobilization. Except for the International Staging System score, both groups were homogeneous regarding the first diagnosis characteristics, first-line treatments, and response parameters. RT metrics (RT yes versus no, volume of irradiated hematopoietic bone marrow [BM], biologically equivalent doses in 2 Gy fractions [EQD2]) were analyzed for the following PBSC outcome parameters: achievement of the PBSC collection goal, CD34+ cell collection yield, duration of the mobilization phase, and number of leukapheresis (LP) sessions to reach the collection goal. No statistically significant differences in the percentage of collection failures to reach at least 3 sufficient PBSC transplants were identified comparing patients with (n = 32 [11%]) and without RT (n = 4 [6%]) before PBSC mobilization (P = .265). However, patients with RT before PBSC mobilization showed a significant prolongation of the PBSC mobilization (median 1 day, P =.026) and required a higher number of LP sessions to reach the collection goal (median 1 LP, P < .001) compared with patients who received RT after PBSC mobilization. Moreover, patients with RT before PBSC mobilization reached a significantly lower CD34+ cell collection result (mean 8.94 versus 9.81 × 106/kg body weight [bw], P = .002). No correlation was identified between the overall CD34+ cell yield and the volume of irradiated hematopoietic BM or EQD2, respectively. In the RT before PBSC mobilization group, patients who required more than 1 LP session to reach the PBSC collection goal after RT had a significantly higher percentage of radiated hematopoietic BM compared to those who required only 1 LP session (mean 9.7% versus 7.2%, P = .002). Overall, our study indicates a negative impact of RT on PBSC mobilization and collection. Apart from emergency settings, it might be beneficial to postpone RT to a post-PBSC collection time point. © 2021 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

Erratum: Commentary: Autologous Peripheral Blood Stem Cells (PBSC) are Safe and Effective in Knee Osteoarthritis.

[This corrects the article DOI: 10.3389/fphar.2020.00404.].

Grade 2 acute GVHD is a factor of good prognosis in patients receiving peripheral blood stem cells haplo-transplant with post-transplant cyclophosphamide.

BACKGROUND: The impact of acute graft versus host disease (GVHD) on survivals for patients receiving a haploidentical allogeneic stem-cell transplant (Allo-SCT) with peripheral blood stem-cells (PBSC) complemented by post-transplant cyclophosphamide (PTCY) is ill-known. MATERIAL AND METHODS: This retrospective study included 131 patients who received a PBSC haplograft in order to precise the impact of acute GVHD on outcomes. There were 78 males and 53 females and the median age for the whole cohort was 59 years (range: 20-71). Thirty-five patients were allografted for a lymphoid disease and 96 for a myeloid malignancy, including 67 patients with acute myeloid leukemia (AML). RESULTS: The cumulative incidence (CI) of day 100 grade 2-4 and 3-4 acute GVHD was 43.4 + 4.6% and 16.7 + 3.4%, respectively. The 2-year CI of moderate/severe chronic GVHD was 10.1 + 2.8%. The only factor affecting the occurrence of GVHD was GVHD prophylaxis. Indeed, CI of day 100 grade 2-4 (but not grade 3-4) acute GVHD was significantly reduced when adding anti-thymoglobulin (ATG) to PTCY. However, in multivariate analysis, grade 2 acute GVHD was significantly associated with better disease-free (HR: 0.36; 95%CI: 0.19-0.69, p = .002) and overall (HR: 0.35; 95%CI: 0.1-0.70, p = .003) survivals. The same results were observed when considering only AML patients. CONCLUSION: Acute grade 2 GVHD is a factor of good prognosis after PBSC haplotransplant with PTCY. Further and larger studies are needed to clarify the complex question of GVHD prophylaxis in the setting of haplo-transplant, especially that of combining ATG and PTCY.

A new protocol for improving efficiency of autologous peripheral blood stem cell collection in patients with high white blood cell counts.

BACKGROUND: Collection efficiency (CE) of peripheral blood stem cell (PBSC) collections is negatively affected by increasing white blood cell (WBC) counts of the patient. This study compared a new optimized mononuclear cell (MNC) collection protocol (OPP) to the standard MNC collection protocol recommended by the manufacturer (STP) for PBSC collection in patients with WBC counts >35 000/µL. STUDY DESIGN AND METHODS: Single-center, retrospective, and observational study of 81 autologous PBSC collections on Fenwal Amicus cell separators in 70 adult patients. RESULTS: Median peripheral WBC count (×103 /µL; 44.2 in OPP group vs 46.5 in STP group) and median CD34+ count (105/µL in OPP group vs 40/µL in STP group) at the beginning of PBSC collection did not differ significantly. Median CE2 (45% vs 31%; P < .001) as well as CD34+ yield of the apheresis product both with regards to median absolute CD34+ content (×106 ; 793 vs 188; P = .001) as well as median CD34+ content (×106 )/kg body weight (8.93 vs 2.51; P = .002) were significantly higher for the OPP. Overall, 18/21 (86%) patients with the OPP obtained their target CD34+ amount with a single apheresis session, compared to 25/50 (50%) with the STP (P = .005). PBSC collections using OPP lasted significantly longer (median 377 minutes vs 260 minutes; P < .001) than with the STP. CONCLUSIONS: The OPP significantly improves CE2 for PBSC collections on Fenwal Amicus cell separators in patients with pre-apheresis WBC counts >35 000/µL and significantly reduces the necessity for multiple apheresis sessions. The OPP is therefore suited to reduce both patient burden and cost in autologous PBSC collection.

Midline catheter as effective device in healthy allogeneic donors and patients without an adequate peripheral venous access for HPC collection by apheresis: Preliminary experience at IEO.

Collection of HPC by apheresis requires adequate venous access for inflow and for outflow. The use of midline has never been reported in this setting. We prospectively analyzed the use of midline for performing apheresis on 3 healthy donors and 3 adults patients requiring autologous transplantation. A total of 8 polyurethane midlines, with an external diameter of 5 French, was inserted (2 midlines in both arms in 2 healthy donors) by our PICC team the day before apheresis and removed at the end of target collection. Mean flow rate was 35 ml/min. Target cellular dose was reached in all patients / donors with a maximum of 2 procedures without any complications. Midline is effective and safe for HPC collection either in donors or patients avoiding the placement of a central venous catheter.