[Comparison of etoposide combined with G-CSF and cyclophosphamide combined with G-CSF in the mobilization of autologous peripheral blood stem cells in patients with multiple myeloma].

Objective: The effect and safety of etoposide combined with G-CSF were compared with those of cyclophosphamide combined with G-CSF in autologous peripheral blood mobilization in patients with multiple myeloma (MM) . Methods: Patients with MM who received autologous peripheral blood stem cell mobilization and collection in the Department of Hematology, Beijing Chaoyang Hospital Affiliated to Capital Medical University from January 1, 2020 to July 31, 2023 were included. A total of 134 patients were screened by propensity score matching technology according to a 1∶1 ratio. A total of 67 cases were each treated with ETO combined with G-CSF mobilization scheme (ETO group) and CTX combined with G-CSF mobilization scheme (CTX group). Their clinical data were retrospectively analyzed. Results: ①Collection results: the ETO and CTX groups [2 (1-3) d vs 2 (1-5) d; P<0.001] and CD34(+) cells [7.62×10(6) (2.26×10(6)-37.20×10(6)) /kg vs 2.73×10(6) (0.53×10(6)-9.85×10(6)) /kg; P<0.001] were collected. The success rate of collection was 100.0% (67/67) versus 76.1% (51/67) (P<0.001). Excellent rate of collection was 82.1% (55/67) versus 20.9% (14/67; P<0.001). Two patients in the ETO group switched protocols after 1 day of collection, and 11 patients in the CTX group switched protocols after 1-2 days of collection. ②Adverse reactions: granular deficiency with fever (21.5%[14/65] vs. 10.7%[6/56]; P=0.110), requiring platelet transfusion [10.7% (7/65) vs 1.8% (1/56) ; P=0.047]. ③Until the end of follow-up, 63 cases in the ETO group and 54 cases in the CTX group have undergone autologous transplantation. The median number of CD34(+) cells infused in the two groups was 4.62×10(6) (2.14×10(6)-19.89×10(6)) /kg versus 2.62×10(6) (1.12×10(6)-5.31×10(6)) /kg (P<0.001), neutrophil implantation time was 11 (9-14) d versus 11 (10-14) d (P=0.049), and platelet implantation time was 11 (0-19) d vs. 12 (0-34) d (P=0.035). One case in the CTX group experienced delayed platelet implantation. Conclusion: The mobilization scheme of etoposide combined with G-CSF requires relatively platelet transfusion, but the collection days are shortened. The collection success rate, excellent rate, and the number of CD34(+) cells obtained are high, and the neutrophil and platelet engraftment is accelerated after transplantation.

Small but mighty: Case report and practical guidance for peripheral blood stem cell collection in small infants.

Modern apheresis devices, with increased procedural precision, automation, and monitoring, have been shown to allow for safe delivery of apheresis therapies in young children. Medical advances are increasing demand for apheresis procedures like mononuclear cell collection in infants <10 kg, including stem-cell supported chemotherapy, cell collection for chimeric antigen receptor T cell development, and now ex vivo gene therapies for rare genetic diseases. Nevertheless, safe delivery in small infants involves a range of unique considerations and challenges, beyond just size, and experience will vary between centers. In this case report we describe our experience performing mononuclear cell collection in our smallest patient to date and outline a practice guideline developed following a literature review and discussion with both international experts and device representatives. This case may help to inform other clinicians aiming to provide apheresis care to very small infants in their own centers.

Predictive factors for peripheral blood stem cell mobilization in multiple myeloma in the era of novel therapies: A single-center experience.

OBJECTIVE: Multiple myeloma (MM) is the leading indication of autologous hematopoietic stem cell transplantation. The aim of this study was to determine the incidence of mobilization failure and characterize the risk factors associated with poor mobilization (PM) of MM patients in novel therapies era. METHODS: We conducted a retrospective study of 211 MM patients who received their first peripheral blood stem cells (PBSC) mobilization at our single center. The following data were collected: age, gender, clinical stage, disease status, complete blood cell count, induction regimen, CD34+ cell count in peripheral blood (PB), and PBSC collections. RESULTS: In addition to conventional drugs, 22 (10.4%) patients received daratumumab containing induction, and 33 (15.6%) patients used plerixafor for poor mobilization (pre-apheresis PB CD34+ cells <20/µL). Failure of collection occurred in 24 (11.4%) patients and was correlated with low white blood cell (WBC), ≥3 cycles of lenalidomide treatment before mobilization, steady-state mobilization and nouse of plerixafor are associated with mobilization failure. Daratumumab-based induction treatment ≥2 courses, albumin >41 g/L before mobilization, and steady-state mobilization were risk factors for PM in subgroups of patients treated with lenalidomide for <3 courses. In addition, Hepatitis B virus infection at baseline, thalassemia and measurable residual disease positivity were recognized as predictive factors for PM in subset of chemo-mobilization patients. CONCLUSION: In addition to some well-recognized risk factors, baseline WBC count and daratumumab exposure ≥2 courses before mobilization were revealed as the predictive factors of mobilization failure, providing consultation for preemptive use of plerixafor.

[Usefulness of web-based application for health surveys before and after peripheral blood stem cell harvest from healthy donors].

Health surveys to assess adverse events after peripheral blood stem cell harvest (PBSCH) have conventionally been conducted by phone, but phone calls are suboptimal for conducting frequent surveys. We developed a web-based application (donor app) that enables donors to inform healthcare professionals (HCPs) of their health status as an electronic patient-reported outcome (ePRO). In this prospective observational study, we compared the usefulness of this donor app to phone calls for conducting health surveys. App users reported ePRO daily, and patients called by HCPs reported their health status at least once a week when called. The observation period was from the first administration of granulocyte colony-stimulating factor to the first follow-up visit after PBSCH, excluding the hospitalization period. Each group consisted of eight donors with a median age of 32 years (range: 19-58). Nine (56.3%) were female. There were eight related donors in the phone call group and four in the donor app group. During the observation period, HCPs obtained health status reports more frequently from app users than from phone call recipients (mean proportion of days with reports made during the observation period, 27.0% vs 53.5%; p<0.05). Average time spent by the HCPs for one follow-up and total follow-ups were both significantly shorter when the donor app was used. There were no differences in donor burden or satisfaction with donation. Our study suggests that use of a donor app could provide more detailed health survey data without increasing the burden on donors and HCPs.

Personalized autologous stem cell harvesting improves patient collection outcomes.

OBJECTIVES: This study aims to demonstrate that utilizing a personalized approach to apheresis stem cell collection, can safely optimize the collection outcomes, especially in the context of poor mobilizers and high cell targets. BACKGROUND: The optimal mobilization and harvesting of peripheral blood stem cells is critical to the success of the stem cell transplant. The ideal strategy that promotes better cell yields, with sustainable use of resources and assuring patient safety, should be pursued. METHODS: PBSC collections for autologous stem cell transplant data according to a fixed-processed volume strategy (One Size Fits All) or individualized to patients CD34+ peripheral blood content and target approach (Custom-Tailored or CT) were retrospectively compared. RESULTS: A total of 263 collections from 142 patients were assessed. The majority of patients were male, had multiple myeloma and were mobilized with isolated G-CSF. The CT strategy promoted a significantly higher CD34+ cell yield when the pre-collection CD34 was lower than 20/µl (1.02 ± 0.16 versus 1.36 ± 0.23, p < 0.001) and also a decrease in the proportion of mobilization cycles that needed 3 apheresis (31% versus 14%, p = 0.02). There was no difference in apheresis-related adverse events between the groups. CONCLUSION: Tailoring the apheresis procedures to the patient-specific characteristics and objectives, can effectively promote better patient outcome.

A case of acute lung injury in a peripheral blood stem cell donor mobilized with pegylated recombinant human granulocyte colony-stimulating factor.

Pegylated recombinant human granulocyte colony-stimulating factor (PEG-rhG-CSF) has been introduced for the mobilization of peripheral blood stem cells (PBSCs). However, no cases of acute lung injury (ALI) in healthy donors have been reported, and the underlying mechanisms remain poorly understood. We first reported a case of ALI caused by PEG-rhG-CSF in a healthy Chinese donor, characterized by hemoptysis, hypoxemia, and patchy shadows. Ultimately, hormone administration, planned PBSC collection, leukocyte debridement, and planned PBSC collection resulted in active control of the donor's ALI. The donor's symptoms improved without any adverse effects, and the PBSC collection proceeded without incident. Over time, the lung lesion was gradually absorbed and eventually returned to normal. PEG-rhG-CSF may contribute to ALI in healthy donors via mechanisms involving neutrophil aggregation, adhesion, and the release of inflammatory mediators in the lung. This case report examines the clinical manifestations, treatment, and mechanism of lung injury induced by PEG-rhG-CSF-mobilized PBSCs.

Allogeneic transplantation of bone marrow versus peripheral blood stem cells from HLA-identical sibling donors for hematological malignancies in 6064 adults from 2003 to 2020: different impacts on survival according to time period.

BACKGROUND: Mobilized peripheral blood stem cells (PBSC) have been widely used instead of bone marrow (BM) as the graft source for allogeneic hematopoietic cell transplantation (HCT). Although early studies demonstrated no significant differences in survival between PBSC transplantation (PBSCT) and BM transplantation (BMT) from human leukocyte antigen (HLA)-identical sibling donors to adults with hematological malignancies, recent results have been unclear. OBJECTIVE: The objective of this retrospective study was to compare overall survival (OS), relapse, non-relapse mortality (NRM), hematopoietic recovery and graft-versus-host disease (GVHD) between PBSCT and BMT according to the time period of HCT (2003-2008, 2009-2014, or 2015-2020). STUDY DESIGN: We retrospectively compared the outcomes after PBSCT versus BMT in 6064 adults with hematological malignancies using a Japanese registry database between 2003 and 2020. RESULTS: The adjusted probability of OS was significantly higher in BMT recipients compared to PBSCT recipients during the early period of 2003-2008 (adjusted hazard ratio [HR], 0.79; 95% confidence interval [CI], 0.70-0.91; P < 0.001) and the middle period of 2009-2014 (adjusted HR, 0.80; 95% CI, 0.70-0.91; P < 0.001). However, during the late period of 2015-2020, the adjusted probability of OS was comparable between BMT and PBSCT recipients (adjusted HR, 0.94; 95% CI, 0.79-1.13; P = 0.564), which were mainly due to the reduction of NRM. There was no significant difference in the relapse rate between the groups, irrespective of the time period. Compared to BMT, PBSCT led to faster neutrophil and platelet recovery and the cumulative incidences of grades II-IV and grades III-IV acute and overall and extensive chronic GVHD were significantly higher in PBSCT recipients, irrespective of the time period. CONCLUSIONS: PBSCT and BMT had similar survival outcomes and relapse rates in adult patients with hematological malignancies during the late time period of 2015-2020 despite the hematopoietic recovery and acute and chronic GVHD being higher in PBSCT recipients in all time periods.

Autologous peripheral blood stem cell mobilization and apheresis in pediatric patients with cancer: A single-center report of 64 procedures.

BACKGROUND: The published experience concerning autologous peripheral blood stem cell collection in children is very limited. METHODS: The data of pediatric patients who underwent autologous stem cell mobilization and apheresis between January 2011 and April 2020 were analyzed retrospectively. RESULTS: We studied retrospectively 64 mobilization and apheresis procedures in 48 pediatric patients (34 males, 14 females), mean age of 7.31 ± 5.38 (range, 1.5-19.7) years, the underlying disease was mostly neuroblastoma (NBL). The body weight of 21 patients (43.75%) was 15 kg or less. The targeted autologous peripheral stem cell apheresis (APSCA) was successfully achieved in 98% of patients. Neuroblastoma patients were younger than the rest of the patients and underwent apheresis after receiving fewer chemotherapy cycles than others and all of them mobilized within the first session successfully. Plerixafor was added to mobilization in nine heavily pretreated patients (18.7%), median two doses (range, 1-4 doses). 11 patients (22.9%) underwent radiotherapy (RT) before mobilization with doses of median 24 Gy (range, 10.8-54.0 Gy). Patients with RT were older at the time of apheresis and had received more chemotherapy courses than patients without RT. As a result, patients with a history of RT had significantly lower peripheral CD34+ cells and CD34+ yields than those without RT. In 17 patients (35.4%), 22 different complications were noted. The most common complications were catheter-related infections (n:10, 20.8%), followed by catheter-related thrombosis in eight patients (16.7%). CONCLUSIONS: Patients who had far less therapy before apheresis were more likely to mobilize successfully. Our study provides a detailed practice approach including complications during APSCA aiming to increase the success rates of apheresis in transplantation centers.

Pain is what hurts: An exploration of perception and management of pain in peripheral blood stem cell donors.

BACKGROUND: Pain is a side effect of Granulocyte-Colony Stimulating Factor (G-CSF) administration. This prospective study investigates various aspects including pain perception occurring in Peripheral Blood Stem Cell (PBSC) donors. MATERIALS AND METHODS: Related and unrelated PBSC donors were prospectively studied. Donors recorded pain symptoms during the four-day period of G-CSF administration using the McGill Pain Questionnaire, a Visual Analog Scale and a pain diary. RESULTS: There were 208 donors included, 102 (49%) related and 106 (51%) unrelated donors. Ninety-two percent of all reported the occurrence of pain. Moderate or severe pain was reported by 52%. No differences were found between related and unrelated donors. Pain occurred more often in females (p = 0.035). Relatively young donors (age 16-30 years) more frequently showed to have pain in comparison to older donors (>50 years) (p = 0.006). Musculoskeletal pain was most frequently distributed in the gluteal and lower back region (65-71%). Irrespective of the pain location, pain was most often described as nagging, annoying, however tolerable. Donors experiencing pain most on days of G-CSF administration, most frequently occurring during relaxation or at night. Sleep-mode was often affected. The use of paracetamol (acetaminophen) was sufficient for all but one donor. CONCLUSION: This is the first study to describe different aspects of pain associated with G-CSF administration in donors. Although the observed pain was tolerable, it should never be neglected. Knowledge derived from this study is of use for staff members involved in donor information and care management.

[Research Progress on the Application Strategies of Plerixafor in the Peripheral Blood Stem Cell Mobilization for Autologous Transplantation--Review].

Plerixafor, an analog of C-X-C motif chemokine receptor 4 (CXCR4), which allows the release of stem cells from the bone marrow into peripheral blood (PB) by disrupting the interaction of CXCR4 with stromal cell-derived factor-1 (SDF-1), is effective in mobilization for peripheral blood stem cells (PBSC). Due to its market approval has not been long and its high price in China, the clinical application of plerixafor is still very limited. The clinicians are actively seeking the optimal use of plerixafor to improve the success rate of PBSC collection and reduce the cost. This article reviews the latest research progress related to plerixafor application, in order to summarize the optimal use of plerixafor in autologous hematopoietic stem cell transplantation (auto-HSCT).

Identifying optimal candidates for autologous peripheral blood stem cell therapy in patients with decompensated liver cirrhosis: a prognostic scoring system.

BACKGROUND: Stem cell transplantation shows great potential to improve the long-term survival of cirrhosis patients. However, therapeutic effects may not be homogeneous across the whole study population. This study constructed an easy-to-use nomogram to improve prognostic prediction and aid in treatment decision making for cirrhotic patients. METHODS: From August 2005 to April 2019, 315 patients with decompensated cirrhosis receiving autologous peripheral blood stem cell (PBSC) transplantation were enrolled in this study. They were randomly classified into training (2/3) and validation (1/3) groups. A predictive model was developed using Cox proportional hazard models and subsequently validated. The predictive performance of the model was evaluated and also compared with other prognostic models. RESULTS: Age, creatinine, neutrophil-to-lymphocyte ratio, and Child-Turcotte-Pugh class were included in the nomogram as prognostic variables. The nomogram showed high discrimination power concerning the area under receiver operating characteristic curves (3/5-year AUC: 0.742/0.698) and good consistency suggested by calibration plots. Patients could be accurately stratified into poor- and good-outcome groups regarding liver-transplantation free survival after receiving PBSC therapy (P < 0.001). Compared with poor-outcome group, the liver function of patients listed for liver transplantation in the good-outcome group was significantly improved (P < 0.001). Besides, our nomogram achieved a higher C-index (0.685, 95% CI 0.633-0.738) and better clinical utility compared with other conventional prognostic models. CONCLUSIONS: The proposed nomogram facilitated an accurate prognostic prediction for patients with decompensated cirrhosis receiving PBSC transplantation. Moreover, it also held the promise to stratify patients in clinical trials or practice to implement optimal treatment regimens for individuals.

Incidence of cardiovascular disease in healthy Swedish peripheral blood stem cell donors - a nationwide study.

Granulocyte colony-stimulating factor (G-CSF) is used in a majority of healthy donors to obtain peripheral blood stem cells for allogeneic stem cell transplantation. Since high levels of G-CSF activates endothelial cells and can induce a pro-coagulatory state, and fuelled by case reports of cardiovascular events in donors, some concerns have been raised about a potential for an increased risk of cardiovascular events for the donors after donation. We studied the incidence of cardiovascular disease following stem cell donation in a Swedish national register based cohort of 1098 peripheral blood stem cell donors between 1998 and 2016. The primary objective was to evaluate if the incidence of cardiovascular disease was increased for donors treated with G-CSF. The incidence of any new cardiovascular disease was 6.0 cases per 1000 person years, with a median follow up of 9.8 years. The incidence did not exceed that of age- sex- and residency-matched population controls (hazard ratio 0.90, 95% confidence interval (CI) 0.76-1.07, p-value 0.23), bone marrow donors, or non-donating siblings. Long-term cardiovascular disease incidence was not increased in this national register based study of peripheral blood stem cell donors treated with G-CSF.

Safety and efficacy of peripheral blood stem cells collection in healthy children and pediatric patients with thalassemia major weighing 20 kg or less.

BACKGROUND: Peripheral blood stem cell (PBSC) collection in children poses challenges due to their small size, low body weight (BW), and unique pediatric physiology, especially among children weighing 20 kg (kg) or less. METHODS: PBSC collection data of both healthy children and patients with thalassemia major (TM) weighing 20 kg or less between January 2013 and December 2020 were reviewed. Moreover, PBSCs characteristics along with various aspects of efficiency and safety between healthy donors and patients with TM were compared. RESULTS: A total of 262 PBSC procedures were performed on 255 children. Of these, 91 procedures were carried out on 85 allogeneic healthy donors, and 171 auto-backup collections were performed on 170 patients with TM to ensure PBSC availability and prevent transplantation failure. A minimum pre-apheresis hemoglobin (HGB) level of 60 g/L was discovered to be safe and feasible in patients with TM. The median CD34+ cell dose in the PBSC product during the initial apheresis procedure was higher in healthy donors compared to patients with TM (7.29 ± 5.28 × 106 cells/kg vs5.88 ± 4.23 × 106 cells/kg, P = .043). The total CD34+ cells/kg recipient weight exhibited a positive correlation with pre-apheresis monocyte counts, but a negative correlation with donor weight. Apheresis significantly reduced hematocrit and platelet counts in the allogeneic group compared to the autologous group. Patients with TM experienced a higher occurrence of bone pain related to granulocyte colony-stimulating factor treatment. Notably, no serious complications related to PBSCs mobilization, central venous catheter placement, or the apheresis procedure were observed in either group. CONCLUSIONS: PBSCs collection was both safe and effective in healthy children and pediatric patients with TM weighing 20 kg or less.

Similar efficacy outcomes with peripheral blood stem cell versus bone marrow for autologous stem cell transplantation in acute myeloid leukemia: Long-term follow-up of the EORTC-GIMEMA randomized AML-10 trial.

We report here the long-term follow-up of the only prospective randomized trial of autologous hematopoietic stem cell transplantation (auto-HSCT) with peripheral blood stem cells (APBSCT) versus auto-HSCT with bone marrow (ABMT) in acute myeloid leukemia (AML) patients in first remission (CR). We observed that among patients alive and still in CR 5 years after planned auto-HSCT, approximately 10% of the patients died in the following 10 years. This stresses the need for long-term close surveillance of AML patients after auto-HSCT. Further, long-term follow-up of the trial confirms that APBSCT was comparable to ABMT in term of disease-free-survival and overall survival.

Peripheral blood stem cell collection: Are midline catheters a viable alternative to central venous catheters?

BACKGROUND: Vascular access is a rate-limiting step for peripheral blood stem cell collection. In the absence of readily accessible superficial veins, placement of tunnelled or non-tunnelled central venous catheters (CVCs) is common. These invasive access routes create medical risks for patients and are associated with logistical challenges, thus prompting a search for alternatives. One such option is the off-label use of midline catheters. STUDY DESIGN AND METHODS: We carried out a literature search for published experience with the use of midline catheters for peripheral blood stem cell collection. Data extracted included whether collections were allogeneic or autologous, donor sex, age and weight, inlet flow rate, total blood volumes (TBV) processed, collection duration, number of collections per donor, and achievement of collection targets. RESULTS: The search produced three reports (one in abstract form) comprising 19 patients and 26 collection events. Donor sex and status were provided for 18 patients; 10 were female, 8 were male, 12 were allogeneic, and 6 autologous. Median (range) for: donor age was 28 (12-59); donor body weight (kg) was 77.5 (45.4-113.4); inlet flow rate (in mL/min) was 66 (28-80); TBV processed (in mL) was 15,880 (6178-21,871); collection duration (in hours) was 5.0 (3.2-7.0); and CD34 × 106/kg collection yield was 5.9 (3.6-23.0). Target CD34 yields were achieved in 14/19 (74%) of donors with 7/19 (37%) requiring two collections days. DISCUSSION: Peripheral blood stem cell collection does appear to be viable via midline-based catheter access, particularly for allogeneic donors and shorter collection courses. Development of institution-specific guidelines and care pathways are recommended.

Specificity of HLA monoclonal antibodies and their use to determine HLA expression on lymphocytes and peripheral blood stem cells.

HLA Class I and II expression are known to differ locus-to-locus, however, HLA expression on the cell-surface is frequently reported as the total amount of HLA Class I or II antigens. This is despite evidence that indicates the differential expression of HLA can influence patient outcomes post-transplantation. Although numerous commercially available HLA monoclonal antibodies (mAbs) exist to characterize HLA expression, there is currently a lack of detailed information regarding their reactivities to HLA specificities. The specificities of locus-specific HLA mAbs (nine Class I and four Class II mAbs) were evaluated by two solid-phase Luminex single antigen bead assays. The reactivity patterns of these mAbs were then confirmed by flow cytometry using lymphocytes and PBSCs (peripheral blood stem cells). Out of the 13 HLA mAbs tested, only four (one Class I and three Class II mAbs) displayed intra-locus reactivity without also reacting to inter-locus specificities. Epitope analysis revealed the presence of shared epitopes across numerous HLA loci, explaining much of the observed inter-locus reactivity. The specificity of the HLA mAbs seen in solid-phase assays was confirmed against PBSCs and lymphocytes by flow cytometry. Using this method, we observed differences in the cell surface expression of HLA-C, HLA-DR, HLA-DQ, and HLA-DP between PBSCs and lymphocytes. Our results emphasize the need to characterize the reactivity patterns of HLA mAbs using solid-phase assays before their use on cells. Through understanding the reactivity of these HLA mAbs, the cellular expression of HLA can be more accurately assessed in downstream assays.

Hematopoietic Progenitor Cell Counts of the Leukapheresis Product Determined Using Sysmex XN Analyzers Predict a Sufficient Number of CD34+ Stem Cells in a Peripheral Blood Stem Cell Harvest for Autologous Transplantation.

Objective Several institutions outsource CD34+ cell counting of leukapheresis products, limiting rapid measurements, as results are obtained the next day. This problem is compounded with plerixafor use, a stem cell-mobilizing drug that increases leukapheresis efficiency but requires administration the day before leukapheresis. Use of this drug for a second leukapheresis procedure before the first-day leukapheresis CD34+ count results are confirmed causes unnecessary leukapheresis and expensive plerixafor administration. We investigated whether or not measuring hematopoietic progenitor cells in leukapheresis products (AP-HPCs) using a Sysmex XN-series analyzer could resolve this problem. Methods We retrospectively compared the absolute AP-HPC value per body weight with the CD34+ (AP-CD34+) count in 96 first-day leukapheresis product samples obtained between September 2013 and January 2021. Comparisons were also conducted according to regimen: granulocyte colony-stimulating factor (G-CSF) monotherapy, chemotherapy plus G-CSF, or plerixafor mobilization. Results AP-CD34+ and AP-HPC counts correlated strongly (rs=0.846) overall and, in particular, under chemotherapy plus G-CSF (rs=0.92) but correlated mildly under G-CSF monotherapy (rs=0.655). AP-HPCs could not completely be dichotomized based on an AP-CD34+ threshold of 2×106/kg for any stimulation procedure. In most cases with AP-HPCs >6×106/kg, the AP-CD34+ count exceeded 2.0×106/kg, but in 5.7% of these cases, the AP-CD34+ count was <2.0×106/kg. A cut-off of AP-HPCs >4.843×106/kg yielded a sensitivity of 71% and specificity of 96% for predicting AP-CD34+≥2×106/kg. Conclusion AP-HPCs can identify cases in which sufficient stem cells have been collected.

Peripheral blood stem cell mobilisation following bortezomib, lenalidomide and dexamethasone induction for multiple myeloma: a real-world single-centre experience.

BACKGROUND: Bortezomib, lenalidomide and dexamethasone (VRd) is now the standard-of-care induction therapy for newly diagnosed transplant-eligible multiple myeloma patients, replacing bortezomib, cyclophosphamide and dexamethasone (VCD) therapy. Lenalidomide can negatively impact stem cell yield because of its myelosuppressive effects, although studies have shown that the latter can be overcome with the use of cyclophosphamide for peripheral blood stem cell (PBSC) mobilisation. AIMS AND METHODS: To investigate whether lenalidomide impacts on PBSC mobilisation and to evaluate the optimal mobilisation strategy post VRd induction, we performed a retrospective review of 56 myeloma patients at a single centre who had PBSC mobilisation between January 2019 and March 2021 and compared three cohorts: (i) VCD induction; mobilisation with granulocyte colony-stimulating factor (G-CSF) alone (n = 23); (ii) four cycles VRd induction; mobilisation with G-CSF and cyclophosphamide (G-CSF + Cyclo) (n = 20); and (iii) three cycles VRd induction; mobilisation with G-CSF alone (n = 13). RESULTS: There was no difference in the mean total CD34 count between VCD and VRd patients who had G-CSF mobilisation (6.27 × 106 /kg vs 5.50 × 106 /kg, P > 0.99). VRd patients mobilised with G-CSF + Cyclo achieved higher mean total CD34 counts compared with G-CSF alone (8.89 × 106 /kg vs 5.50 × 106 /kg, P = 0.04). The majority of VRd patients who had G-CSF + Cyclo (19 of 20; 95%) collected sufficient cells for two or more autologous stem cell transplants (ASCTs), regardless of whether this was required, compared with eight of 13 (62%) VRd patients who had G-CSF alone. CONCLUSION: We conclude that successful PBSC mobilisation for at least one ASCT is possible after three cycles of VRd induction using G-CSF alone. The upfront use of a cyclophosphamide-based mobilisation strategy has a role in patients who have had VRd induction, where the aim is to collect enough stem cells for two or more ASCTs.