A prospective randomized trial of two popular mononuclear cell collection sets for autologous peripheral blood stem cell collection in multiple myeloma

Ethylene oxide-type hypersensitivity reactions in G-CSF mobilized, peripheral blood hematopoietic progenitor cell donors and review

BACKGROUND

Ethylene oxide (EtO) is a volatile, ringed toxic ether used to sterilize heat-labile plastics including apheresis sets. In the 1980s, EtO-associated severe hypersensitivity reactions during hemodialysis led to widespread adoption of alternative sterilization for dialysis kits but not apheresis tubing sets. We now report several cases of EtO-type hypersensitivity reactions in autologous donors undergoing hematopoietic progenitor cell collection (HPCC).

MATERIALS AND METHODS

A 10-year retrospective review of allergic EtO-type reactions in adults undergoing HPCC on the COBE Spectra and SPECTRA Optia was performed. Donor medical history and absolute eosinophil counts were compared between cases and 34 HPCC controls. Published EtO reactions during extracorporeal procedures were reviewed with statistical analysis. Graphics and statistics were performed using commercial software.

RESULTS

Three autologous HPCC donors experienced EtO-type reactions within 15 min of initiating HPCC, for a 10-year incident rate of 0.08% per procedure and 0.18% per donor. All three reactions occurred using the Spectra Optia and IDL tubing set, for an Optia/IDL specific rate of 0.2% per procedure and 0.5% per donor. There was no correlation between EtO reactions, eosinophil counts, or saline prime dwell times. No patient had classic predisposing risk factors for EtO hypersensitivity. Two patients required medical intervention whereas the third responded by pausing the procedure and slowing the inlet rate.

CONCLUSION

EtO-type hypersensitivity reactions can be observed during HPCC, especially with the Optia IDL tubing set. EtO reactions may be missed due to their rarity and staff unfamiliarity with this clinical entity.

Comparison of hematopoietic progenitor cell collection using different inlet flow rates with the Fenwal Amicus

PURPOSE

We have used a hematopoietic progenitor cell (HPC) algorithm (standard [STD]) that restricted the inlet flow rate to 65 mL/min for peripheral white blood cell count (PWBC) >35 × 109 /L (STD). In this study, we evaluated a technique that allows 85 mL/min, regardless of the PWBC count (high). For patients with PWBC >35 × 109 /L, a prospective, randomized comparison of the high flow rate vs the STD PWBC-based flow rate (65 mL/min) was performed, comparing CD34+ and lymphocyte yields, collection efficiencies (CE1), mononuclear cells (MNC), and granulocytes, red blood cell (RBC), and platelet content.

METHODS

The Fenwal Amicus version 4.5 with a heparinized ACD-A anticoagulant (AC) delivered at a 26:1 AC ratio was used. Paired comparisons between high and STD techniques were assessed with Wilcoxon signed rank tests, with P < .05 considered significant. Data are summarized as medians.

RESULTS

Forty patient pairs (autologous) were compared. Diagnoses included primarily multiple myeloma (60%) and lymphoma (37.5%). High had significantly higher median average inlet rates (69 vs 55 mL/min), whole blood processed (20 vs 16 L), and cycles (15 vs 14) than STD. There were no significant differences in pre-procedure counts. Collection contents were (high/STD): 306/328 × 106 CD34+ cells, 48/59% CD34+ CE1 (significant), 0.2/0.2 × 109 /kg lymphocytes, 45/57% lymphocyte CE1, 63/59 × 109 WBC, 15/16 × 109 granulocytes, and 1.9/1.7 × 1011 platelets.

CONCLUSIONS

The simpler, standardized high flow technique did not significantly increase or decrease CD34+ cells or lymphocyte yields, but did significantly decrease CD34+ CE1. The effects on cross-cellular content were minimal and not clinically significant.

Low hematocrit reduces the efficiency of CD34+ cell collection when using the Spectra Optia continuous mononuclear cell collection procedure

BACKGROUND

CD34⁺ cell collection efficiency (CE) is the determining factor when calculating processed blood volume (PBV) for leukapheresis (LP). However, the factors affecting CE in the continuous mononuclear cell collection (cMNC) protocol performed by the Spectra Optia apheresis system are not well established.

STUDY DESIGN AND METHODS

We retrospectively collected the data from 147 consecutive apheresis procedures across 106 healthy donors and 27 patients completed between July 2016 and December 2020 at the Okayama University Hospital. All procedures were performed using the Optia cMNC protocol.

RESULTS

The median CD34⁺ CE2 was significantly higher in the donor samples (64.3%) than in the patient samples (46.8%) (p < .0001). WBC counts, hematocrit, and platelet counts were all significantly higher in the donors than in the patients, and there was a moderate positive correlation between CD34⁺ CE2 and hematocrit (r = .47, p < .0001), with the equation of the line being y = 1.23x + 12.23. In contrast, there was only a very weak correlation between CD34⁺ CE2 and WBC or platelet count. In addition, low hematocrit correlated with an increased time to interface formation.

CONCLUSION

These data revealed the negative impact of low hematocrit on the efficiency of CD34⁺ cell collection when using the Optia cMNC protocol and suggest that hematocrit values should also be considered when determining PBV.

Unstimulated apheresis for chimeric antigen receptor manufacturing in pediatric/adolescent acute lymphoblastic leukemia patients

Autologous unstimulated leukapheresis product serves as starting material for a variety of innovative cell therapy products, including chimeric antigen receptor (CAR)-modified T-cells. Although it may be reasonable to assume feasibility and efficiency of apheresis for CAR-T cell manufacture, several idiosyncrasies of these patients warrant their separate analysis: target cells (mononuclear cells [MNC] and T-cells) are relatively few which may instruct the selection of apheresis technology, low body weight, and, hence, low total blood volume (TBV) can restrict process and product volume, and patients may be in compromised health. We here report outcome data from 46 consecutive leukaphereses in 33 unique pediatric patients performed for the purpose of CD19-CAR-T-cell manufacturing. Apheresis targets of 2×10⁹ MNC/1×10⁹ T-cells were defined by marketing authorization holder specification. Patient weight was 8 to 84 kg; TBV was 0.6 to 5.1 L. Spectra Optia apheresis technology was used. For 23 patients, a single apheresis sufficed to generate enough cells and manufacture CAR-T-cells, the remainder required two aphereses to meet target dose and/or two apheresis series because of production failure. Aphereses were technically feasible and clinically tolerable without serious adverse effects. The median collection efficiencies for MNC and T-cells were 53% and 56%, respectively. In summary, CAR apheresis in pediatric patients, including the very young, is feasible, safe and efficient, but the specified cell dose targets can be challenging in smaller children. Continuous monitoring of apheresis outcomes is advocated in order to maintain quality.

Performance and safety of femoral central venous catheters in pediatric autologous peripheral blood stem cell collection

INTRODUCTION

Autologous peripheral blood hematopoietic progenitor cell collection (A-HPCC) in children typically requires placement of a central venous catheter (CVC) for venous access. There is scant published data regarding the performance and safety of femoral CVCs in pediatric A-HPCC.

METHODS

Seven-year, retrospective study of A-HPCC in pediatric patients collected between 2009 and January 2017. Inclusion criteria were an age ≤ 21 years and A-HPCC using a femoral CVC for venous access. Femoral CVC performance was examined by CD34 collection rate, inlet rate, collection efficiency (MNC-FE, CD34-FE), bleeding, flow-related adverse events (AE), CVC removal, and product sterility testing. Statistical analysis and graphing were performed with commercial software.

RESULTS

A total of 75/119 (63%) pediatric patients (median age 3 years) met study criteria. Only 16% of children required a CVC for ≥ 3 days. The CD34 collect rate and CD34-FE was stable over time whereas MNC-FE decreased after day 4 in 80% of patients. CD34-FE and MNC-FE showed inter- and intra-patient variability over time and appeared sensitive to plerixafor administration. Femoral CVC showed fewer flow-related AE compared to thoracic CVC, especially in pediatric patients (6.7% vs. 37%, P = 0.0005; OR = 0.12 (95%CI: 0.03-0.45). CVC removal was uneventful in 73/75 (97%) patients with hemostasis achieved after 20-30 min of pressure. In a 10-year period, there were no instances of product contamination associated with femoral CVC colonization.

CONCLUSION

Femoral CVC are safe and effective for A-HPCC in young pediatric patients. Femoral CVC performance was maintained over several days with few flow-related alarms when compared to thoracic CVCs.

Adverse events of cryopreserved hematopoietic stem cell infusions in adults: a single-center observational study

BACKGROUND

Autologous hematopoietic stem cell (HSC) transplantation has been used for almost three decades for the management of malignant hematologic diseases and some solid tumors. Dimethyl sulfoxide (DMSO) is used as a cryoprotective agent for hematopoietic progenitor cells (HPCs) collected by apheresis (HPC-A). We evaluated the factors contributing to the occurrence of adverse events (AEs) of cryopreserved HPC-A infusion.

STUDY DESIGN AND METHODS

Between January 2009 and June 2014, a total of 1269 (1191 patients) consecutive HPC-A infusions were given to adult patients undergoing autologous HSC transplantation at Barnes-Jewish Hospital. Only infusions on the first day of transplant were included in the analysis.

RESULTS

AEs were reported in 480 (37.8%) infusions. The most common AEs were facial flushing in 189 (39.4%) infusions, nausea and/or vomiting in 183 (38.1%) infusions, hypoxia requiring oxygen in 139 (29%) infusions, and chest tightness in 80 (16.7%) infusions. Multivariate analysis using logistic regression showed that female sex (odds ratio [OR], 1.78; 95% confidence interval [CI], 1.40-2.26; p < 0.0001), diagnosis other than multiple myeloma (OR, 1.44; 95% CI, 1.12-1.84; p = 0.004), larger volume of infusion per body weight (OR, 1.66; 95% CI, 1.29-2.15; p < 0.0001), and number of granulocytes infused per body weight (OR, 1.30; 95% CI, 1.01-1.67; p = 0.042) were significant predictors of occurrence of AEs during infusion.

CONCLUSION

AEs due to HPC-A infusion occurred in more than one-third of patients. Interventions need to be instituted to reduce AEs and thus improve the safety of HPC-A infusion. Many of these toxicities can be attributed to DMSO, and this is reflected in the volume of infusion. It might be warranted to consider implementing DMSO-reducing protocols before infusion.

Prospective randomized and crossover comparison of two apheresis machines for peripheral blood stem cell collection: a multicenter study

BACKGROUND

Improving apheresis technology may lead to an efficient and safe peripheral blood stem cell (PBSC) collection. Recently, the Spectra Optia (Optia, Terumo BCT) was introduced as an automated apheresis instrument, but comparisons with other instruments have been few. This is the first randomized multicenter and crossover comparison of the Optia with the automated program of the established apheresis instrument, the Spectra (Spectra-Auto, Terumo BCT).

STUDY DESIGN AND METHODS

A total of 233 apheresis procedures performed in 46 autologous patients and 108 allogeneic donors were investigated. Apheresis performed in the first day for all subjects using the Spectra-Auto (n = 79) and the Optia (n = 75) were evaluated as first-day analysis. Seventy-nine subjects, who required another session on the second day, underwent apheresis using the other instrument than the first-day instrument and were compared with each other in a paired crossover analysis.

RESULTS

The two instruments processed similar volumes with comparable run times and volumes of acid-citrate-dextrose used. The volumes of collected products were greater in the Optia. Yields of mononuclear cells and CD34+ cells were not different, but collection efficiencies were higher in the Optia (p = 0.008 in CE1 of crossover analysis). Spectra-Auto-collected products contained more contaminating red blood cells (RBCs), whereas there was a trend of more contaminating platelets (PLTs) in the Optia-collected products. Slight reductions were noted in the RBC or PLT counts of subjects who underwent apheresis with the Spectra-Auto or the Optia, respectively.

CONCLUSION

The Optia is safe and more efficient in the PBSC collection compared with the Spectra-Auto.

[Short-term effects of hemogram in healthy donors after peripheral blood stem cell collection]

目的

探讨连续外周血造血干细胞（PBSC）采集对异基因造血干细胞供者外周血细胞计数的影响以及供者对连续采集的耐受性。

方法

166名于2013至2014年在浙江大学医学院附属第一医院血液科捐献PBSC的亲缘异基因供者，男86名，女80名，中位年龄40.5（15.0~60.0）岁。动员方案为G-CSF 5~10 µg·kg⁻¹·d⁻¹皮下注射至采集结束。于PBSC动员前、采集前、采集1次及2次后检测供者外周血以及采集物中WBC、PLT、HGB。

结果

连续2次PBSC采集后供者外周血HGB中位数由145（94~181）g/L降至138（93~167）g/L（P<0.05），PLT中位数由231（105~490）×10⁹/L降至95（39~210）× 10⁹/L（P<0.05），WBC差异无统计学意义（P>0.05）。采集物中HGB与供者外周血HGB降幅呈低度正相关（r=0.297，P=0.017），采集物中PLT与供者外周血PLT降幅高度相关（r=0.719，P<0.001）。不同年龄组供者在PBSC采集后的HGB降幅两两比较差异无统计学意义（P≥0.05）。PLT差异无统计学意义（P>0.05）。不同体重指数供者在PBSC采集1次及2次后外周血HGB降幅差异均有统计学意义（P=0.003，P<0.001），体重指数<18.5 kg/m²的偏瘦组供者HGB下降最明显（P<0.05）。

结论

健康异基因造血干细胞供者在连续PBSC采集过程中HGB轻度下降，对于偏瘦供者应调整采集参数以保证安全。采集PBSC会使血小板减少的风险增加，减少的程度与年龄及体重指数无关，且均可耐受。

Timing of peripheral blood stem cell yield: comparison of alternative methods with the classic method for CD34+ cell determination

Hematopoietic stem cells (HSCs), still represent a certain mystery in biology, have a unique property of dividing into equal cells and repopulating the hematopoietic tissue. This potential enables their use in transplantation treatments. The quality of the HSC grafts for transplantation is evaluated by flow cytometric determination of the CD34(+) cells, which enables optimal timing of the first apheresis and the acquisition of maximal yield of the peripheral blood stem cells (PBSCs). To identify a more efficient method for evaluating CD34(+) cells, we compared the following alternative methods with the reference method: hematopoietic progenitor cells (HPC) enumeration (using the Sysmex XE-2100 analyser), detection of CD133(+) cells, and quantification of aldehyde dehydrogenase activity in the PBSCs. 266 aphereses (84 patients) were evaluated. In the preapheretic blood, the new methods produced data that were in agreement with the reference method. The ROC curves have shown that for the first-day apheresis target, the optimal predictive cut-off value was 0.032 cells/mL for the HPC method (sensitivity 73.4%, specificity 69.3%). HPC method exhibited a definite practical superiority as compared to other methods tested. HPC enumeration could serve as a supplementary method for the optimal timing of the first apheresis; it is simple, rapid, and cheap.

The impact of recent vincristine on human hematopoietic progenitor cell collection in pediatric patients with central nervous system tumors

BACKGROUND

Central nervous system (CNS) malignancies represent 20% of all childhood cancers. To improve outcomes in infants and children with high-risk disease, treatment can include adjuvant chemotherapy and early autologous peripheral blood human progenitor cell collection (AHPCC), followed by high-dose chemotherapy and stem cell rescue. In many protocols, postoperative chemotherapy includes the administration of weekly vincristine (VCR) between induction chemotherapy cycles, regardless of scheduled AHPCC. We observed anecdotal AHPCC failures in children receiving midcycle VCR (MC-VCR).

STUDY DESIGN AND METHODS

The study was an 8-year retrospective chart review of all children with a CNS malignancy and who underwent AHPCC. Information included patient demographic and clinical data, mobilization regimen, VCR administration, product yields, infusion toxicity, and patient charges. Data were analyzed relative to MC-VCR administration. Graphics and statistical analysis (t-test, chi-square, linear regression) were performed with commercial software.

RESULTS

Twenty-four patients and 47 AHPCCs were available for analysis. Nine patients (37%) received MC-VCR within 7 days of scheduled AHPCC. MC-VCR was associated with delayed marrow recovery (17.9 days vs. 14.9 days, p=0.0012), decreased median peripheral CD34 counts (75 × 10(6) CD34/L vs. 352 × 10(6) CD34/L, p=0.03), decreased median CD34 yields (2.4 × 10(6) CD34/L vs. 17.8 × 10(6) CD34/kg, p=0.08), more AHPCCs per mobilization (2.9 vs. 1.1, p=0.01), and an increased rate of remobilization (33% vs. 6%). Mean patient charges were 2.5× higher in patients receiving MC-VCR than controls (p=0.01).

CONCLUSION

MC-VCR should be withheld before scheduled AHPCC to optimize CD34 collection.

Peripheral blood progenitor cell collection by two programs for autologous and allogeneic transplantation

BACKGROUND

In the Spectra apheresis instrument (Terumo BCT), both manual (Spectra-MNC) and automated (Spectra-Auto) programs have been widely used to collect peripheral blood progenitor cells (PBPCs). However, direct comparison of these programs remains extremely limited.

STUDY DESIGN AND METHODS

We investigated 188 collections and products from autologous (patient) and allogeneic (donor) subjects and analyzed a subset of 89 allogeneic collections and products. Twenty-nine subjects who received apheresis for 2 consecutive days using both programs were also evaluated with a paired crossover comparison.

RESULTS

The two programs processed similar volumes, but run time was longer with Spectra-Auto. Yield and efficiency of CD34+ cell collection were similar between these programs in the whole cohort, although white blood cell (WBC) and mononuclear cell (MNC) yields were higher with Spectra-MNC. In the allogeneic cohort, yield and efficiency of WBC collection were greater in Spectra-MNC. However, collected WBCs, MNCs, and CD34+ cells were similar between these programs in paired comparison. Regardless of program, preapheresis peripheral WBC, MNC, and CD34+ cell counts correlated with the number of cells collected. In contrast, preapheresis WBC counts in the whole cohort were negatively correlated with collection efficiencies of CD34+ cells in Spectra-MNC but not Spectra-Auto. The products collected using Spectra-MNC contained more contaminating platelets (PLTs) than Spectra-Auto, with a corresponding reduction in postdonation circulating PLTs.

CONCLUSION

Spectra-MNC and Spectra-Auto showed distinct features that should be considered on a case-by-case basis. Similar investigations should be undertaken as new collection platforms are introduced.

Safety and efficacy of autologous hemopoietic progenitor cell collection in tandem with hemodialysis in multiple myeloma with myeloma cast nephropathy

Autologous hemopoietic progenitor cell (HPC) collection is the most frequent indication for an apheresis procedure in patients with multiple myeloma, up to 10% of whom may also require hemodialysis because of myeloma kidney. We investigated whether HPC collection could be performed in tandem with hemodialysis, to avoid extra outpatient visits for extracorporeal procedures, without compromising the efficacy of the hemodialysis, the HPC collection efficiency (CE) or patient safety. Four dialysis-dependent patients with multiple myeloma underwent 5 large volume leukapheresis HPC collections in tandem with hemodialysis. Under our protocol, all of the blood processed through the apheresis instrument was dialyzed against a standard calcium-rich bath prior to being returned to the patient, therefore no supplemental calcium was needed. No significant changes in pulse rate (P = 0.625) or mean arterial pressure (P = 0.188) were noted between the start and end of the procedures. The patients exhibited no signs or symptoms of hypocalcemia or other adverse effects. Calculated urea reduction ratios ranged between 62.5 and 73.9%, and HPC CE was between 53 and 84% for 4 of the 5 procedures, indicating that there was no compromise of either procedure when performed in tandem. Ionized calcium measured at the beginning, midpoint and end of every procedure did not change (P = 0.954). The two patients who proceeded to autologous HPC transplant engrafted on Days 11 and 10, respectively. We conclude that autologous HPC collection can safely be performed in tandem with hemodialysis without compromising the efficacy of dialysis, HPC CE, or patient safety.

Limiting the daily total nucleated cell dose of cryopreserved peripheral blood stem cell products for autologous transplantation improves infusion-related safety with no adverse impact on hematopoietic engraftment

Cryopreserved peripheral blood stem cell (PBSC) products can induce a number of infusion-related adverse reactions, including life-threatening cardiac, neurologic, and other end-organ complications. Preliminary analyses suggested limiting the daily total nucleated cell dose infused might decrease the incidence of these adverse effects. A policy change implemented in December 2007, limiting the total nucleated cell (TNC) dose to <1.63 × 10(9) TNC/kg/day, allowed us to assess the impact of this intervention on infusion-related safety, infusion schedules, engraftment, and costs in cohorts of patients undergoing autologous stem cell transplants (ASCTs) 2 years before (325 ASCTs in 288 patients) and 2 years after the policy change (519 ASCTs in 479 patients). The percentage of autologous transplant patients requiring multiple day infusions increased from 6% to 24%. Concurrently, the incidence of infusion-related grade 3-5 severe infusion-related adverse events (SAEs) decreased significantly, from 4% (13 of 325) prepolicy change to 0.6% (3 of 519) postpolicy change (P < .0004). Multiday infusions were not associated with increased time to neutrophil or platelet engraftment or the costs of transplantation. We conclude that limiting the daily TNC dose improved the safety of this procedure without compromising engraftment or increasing the costs of the procedure.

Manual color monitoring to optimize hematopoietic progenitor cell collection on the Fenwal Amicus

A technique was developed to improve consistency of MNC transfers from the centrifuge to the collection bag in the Fenwal Amicus. The operator assures that RBCs completely fill the cassette by the end of the transfer by adjusting the RBC offset in succeeding cycles. We compared yields and crosscellular content before and after implementation of the monitoring technique. Retrospective data from 400 consecutive HPC collection procedures (200 for each technique) were compared. In 40 monitored collections, the RBC offset was adjusted to 6-9 mL to ensure that RBCs completely filled the cassette. Collections requiring these adjustments were not associated with a specific diagnosis. Median values were compared between the 40 collections requiring offset adjustment and those performed before implementation of monitoring. Baseline peripheral CD34+ cell (17 vs. 14 cells μL(-1)), lymphocytes (2 vs. 1.3 × 10(9) /L), WBCs, HCT, and PLTs were significantly higher in the group requiring offset changes. The group requiring offset changes had significantly more CD34+ cells per collection (190.8 × 10(6) or 2.04 × 10(6) /kg vs. 84.3 × 10(6) or 0.89 × 10(6) /kg) and more lymphocytes per collection (16.9 × 10(9) vs. 11.6 × 10(9)). Crosscellular content of the group requiring offset changes was significantly higher for WBCs (41.8 vs. 33.1 × 10(9)), granulocytes (9.6 vs. 7.2 × 10(9)), RBCs (23 vs. 17 mL), and PLTs (2.1 vs. 1.2 × 10(11)). Manual monitoring is a simple, inexpensive method to optimize each HPC collection to maximize CD34+ cell and lymphocyte yields.

Automatic interface-controlled apheresis collection of stem/progenitor cells: results from an autologous donor validation trial of a novel stem cell apheresis device

BACKGROUND

Cryopreserved hematopoietic progenitor cells collected by apheresis from granulocyte-colony-stimulating factor with or without chemotherapy-mobilized patients have become the preferred type of autograft to support treatment of diseases amenable to high-dose chemotherapy. A novel apheresis system, the Spectra Optia v.5.0 (CaridianBCT), was constructed to meet certain shortcomings of manual apheresis systems such as the COBE Spectra MNC (CaridianBCT), including the need for continuous optical or manual monitoring and readjustment of buffy coat position and sensitivity to inconsistent blood flow. By use of optical sensors, which provide real-time automatic interface (buffy coat) and collection line control, the Spectra Optia promises to automatically guide apheresis procedures, potentially freeing up operator time and reducing variability in collection efficiency (CE2).

STUDY DESIGN AND METHODS

In a two-center clinical trial, 35 autologous stem cell donors were subjected to apheresis with the Spectra Optia to validate feasibility and effectiveness of apheresis procedures. Results were compared to data from 80 autologous apheresis procedures with the COBE Spectra MNC.

RESULTS

Usability and function of the automatic interface management were excellent. CD34+ cell quality, assessed by viability staining, colony-forming unit-culture frequency, and engraftment kinetics, was equally good with both systems. CE2 of the Spectra Optia, calculated as CD34+ contents in the product divided by the number of CD34+ cells presented to the collection port, exceeded that of the COBE Spectra MNC. Spectra Optia product volumes were significantly smaller. Very high white blood cell and platelet counts modestly reduced CE2 with the Spectra Optia.

CONCLUSION

The Spectra Optia is a novel automatic apheresis system supporting autologous stem cell collection with at least equal efficiency and superior user-friendliness compared to the COBE Spectra MNC.

Current status of stem cell mobilization

New advances in effective mobilization of peripheral blood stem cells have permitted a greater proportion of patients to benefit from autologous stem cell transplantation. In this review, the relative merits of peripheral blood and mobilized bone marrow are discussed. All available agents are reviewed. A critical assessment of the appropriate dosing and frequency of available growth factors is undertaken, and the most commonly used chemotherapy plus growth factor combinations are covered. Specific recommendations for patients who are poor mobilizers are dealt with including the role of plerixafor.

Predicting PBSC harvest failure using circulating CD34 levels: developing target-based cutoff points for early intervention

PBSCs are usually mobilized using G-CSF with or without chemotherapy. With the emergence of newer mobilizing agents, predicting poor mobilization may allow early intervention and prevent the costs and complications associated with remobilization. We retrospectively evaluated a cohort of 1556 patients seen between January 2000 and September 2008 with multiple myeloma (565; 36%), non-Hodgkin's lymphoma (NHL) (562; 36%), amyloidosis (345; 22%) or Hodgkin's disease (94; 6%), who were initially mobilized with single agent G-CSF. Sensitivity and specificity analysis was used to identify ideal peripheral blood CD34 count (PB-CD34) cutoff points that predicted successful collection. In patients with plasma cell disorders, a PB-CD34 count of 11, 17, 21 and 28/μL by day 4 or 5 was required to collect a target of 2, 4, 8 or 12 million cells/kg, respectively. A CD34 yield of <0.8 million cells/kg on first apheresis also predicted for <2 million CD34 cells/kg. For patients with NHL or Hodgkin's disease, a PB-CD34 count of <6 and <15/μL on day 4 or 5 predicted failure to achieve a target collection of 2 and 4 million cells/kg, respectively. This study suggests that PB-CD34 thresholds should be based on collection target to allow for early intervention and to prevent collection failures.