Loss of CD34+ Cells and Effect of the Number of Viable Cryopreserved CD34+ Cells in the Infused Blood Grafts on Hematologic Recovery, Progression-Free Survival and Overall Survival in NHL Patients After Autologous Stem Cell Transplantation.

PATIENTS: This post-hoc study aimed to find out factors affecting graft viable CD34+ cell loss during processing and cryopreservation in 129 non-Hodgkin lymphoma (NHL) patients receiving autologous stem cell transplantation (auto-SCT) and the impact of a low (< 2.0 × 106/kg, group A) and a decent number (≥ 2 × 106/kg, group B) of viable CD34+ cells infused on the hematologic recovery, progression-free survival (PFS) and overall survival (OS) after auto-SCT. RESULTS: The median loss of viable CD34+ cells during cryopreservation was higher in group A (47% vs. 19%, p < .001). A higher yield of CD34+ cells at the first apheresis in group B (p = .002) was linked with greater loss of viable graft CD34+ cells after cryopreservation. Filgrastim (FIL) use for mobilization seemed to associate with higher viable CD34+ cell loss compared to pegfilgrastim (PEG) or lipegfilgrastim (LIPEG) in both groups (in group A FIL 66 vs. PEG 35%, p = .006; in group B FIL 37 vs. PEG 15 vs. LIPEG 13%, p < .001). Hematologic recovery after auto-SCT was faster in group B. Neither viable CD34+ cell loss during storage nor viable CD34+ cell number < 2.0 × 106/kg infused affected on PFS or OS. CONCLUSIONS: G-CSF type used in mobilization and mobilization capacity were found to correlate with viable CD34+ cell loss during processing and storage. Most importantly, low infused viable CD34+ cell count did not seem to impact on PFS or OS.

Impact of the number of cryopreserved CD34+ cells in the infused blood grafts on hematologic recovery and survival in myeloma patients after autologous stem cell transplantation: Experience from the GOA study.

BACKGROUND: Prospective data on the impact of CD34+ cell loss during cryopreservation and the amount of cryopreserved CD34+ cells infused after high-dose therapy on hematologic recovery and post-transplant outcome in multiple myeloma (MM) are scarce. PATIENTS AND METHODS: This post-hoc study aimed to investigate factors associating with CD34+ cell loss during cryopreservation and the effects of the infusion of a very low number (<1.0 × 106 /kg, group A), low number (1-1.9 × 106 /kg, group B), and optimal number (≥2 × 106 /kg, group C) of thawed viable CD34+ cells on hematologic recovery, progression free survival, and overall survival after autologous stem cell transplantation among 127 patients with MM. RESULTS: In group C, pegfilgrastim use (P = 0.001), plerixafor use (P = 0.039), and older age ≥ 60 years (P = 0.026) were associated with less loss of CD34+ cells during cryopreservation. Better mobilization efficacy correlated with greater CD34+ cell loss in group B (P = 0.013 and P = 0.001) and in group C (P < 0.001 and P < 0.001). Early platelet engraftment was slowest in group A (20 d vs 12 d in group B vs 11 d in group C, P = 0.003). The infused viable CD34+ cell count <1.0 × 106 /kg seemed not to have influence on PFS (P = 0.322) or OS (P = 0.378) in MM patients. CONCLUSIONS: Cryopreservation impacts significantly on the CD34+ cell loss. A very low number of graft viable CD34+ cells did not affect PFS or OS.

Autograft cellular composition and outcome in myeloma patients: Results of the prospective multicenter GOA study.

BACKGROUND: Autologous stem cell transplantation (auto-SCT) is a widely used treatment option in multiple myeloma (MM) patients. The optimal graft cellular composition is not known. STUDY DESIGN AND METHODS: Autograft cellular composition was analyzed after freezing by flow cytometry in 127 MM patients participating in a prospective multicenter study. The impact of graft cellular composition on hematologic recovery and outcome after auto-SCT was evaluated. RESULTS: A higher graft CD34+ cell content predicted faster platelet recovery after auto-SCT in both the short and long term. In patients with standard-risk cytogenetics, a higher graft CD34+ count (>2.5 × 106 /kg) was linked with shorter progression-free survival (PFS; 28 vs. 46 months, p = 0.04), but there was no difference in overall survival (OS) (p = 0.53). In a multivariate model, a higher graft CD34+ CD133+ CD38- (>0.065 × 106 /kg, p = 0.009) and NK cell count (>2.5 × 106 /kg, p = 0.026), lenalidomide maintenance and standard-risk cytogenetics predicted better PFS. In contrast, a higher CD34+ count (>2.5 × 106 /kg, p = 0.015) predicted worse PFS. A very low CD3+ cell count (≤20 × 106 /kg, p = 0.001) in the infused graft and high-risk cytogenetics remained predictive of worse OS. CONCLUSIONS: Autograft cellular composition may impact outcome in MM patients after auto-SCT. More studies are needed to define optimal graft composition.

Mobilization characteristics, blood graft composition, and outcome in diffuse large B-cell lymphoma after autologous stem cell transplantation: Results from the prospective multicenter GOA study.

BACKGROUND: Diffuse large B-cell lymphoma (DLBCL) is a common indication for autologous stem cell transplantation (auto-SCT). STUDY DESIGN AND METHODS: This prospective noninterventional study aimed to evaluate the impact of mobilization characteristics and graft cellular content on hematologic recovery and outcome after auto-SCT among 68 patients with DLBCL. RESULTS: Better mobilization capacity as manifested by blood CD34+ cell count >32 × 106 /L and CD34+ cell yield of the first apheresis >2.75 × 106 /kg correlated with faster neutrophil (P = .005 and P = .017) and platelet (P = .002 and P < .001) recovery. A higher number of infused CD34+ cells (> 2.65 × 106 /kg) was associated with better 5-year overall survival (OS; 95% vs 67%, P = .012). The graft CD34+ CD133+ CD38- cell count >0.07 × 106 /kg was predictive of better 5-year OS (87% vs 63%; P = .008) and higher graft CD3+ cell count (>23.1 × 106 /kg) correlated also with better 5-year OS (80% vs 40%, P = .008). In multivariate analysis only disease status of CR I at auto-SCT was associated with better progression-free survival (P = .014) and OS (P = .039). CONCLUSION: The mobilization capacity of CD34+ cells impacted on early hematologic recovery in patients with DLBCL after auto-SCT. Higher graft CD34+ cell count and both CD34+ CD133+ CD38- and CD3+ cells were also associated with better OS. The effect of optimal graft cellular composition on outcome in DLBCL should be evaluated in a randomized study.

Blood Graft and Outcome After Autologous Stem Cell Transplantation in Patients With Primary Central Nervous System Lymphoma.

BACKGROUND: Autologous stem cell transplantation (auto-SCT) is a treatment option for patients with primary central nervous system lymphoma (PCNSL). METHODS: In this prospective multicenter study, the effects of blood graft cellular content on hematologic recovery and outcome were analyzed in 17 PCNSL patients receiving auto-SCT upfront. RESULTS: The infused viable CD34+ cell count > 1.7 × 106/kg correlated with more rapid platelet engraftment (10 vs. 31 days, P = 0.027) and with early neutrophil recovery (day + 15) (5.4 vs. 1.6 × 109/L, P = 0.047). A higher number of total collected CD34+ cells > 3.3 × 106/kg infused predicted worse 5-year progression-free survival (PFS) (33% vs. 100%, P = 0.028). In addition, CD3+CD8+ T cells > 78 × 106/kg in the infused graft impacted negatively on the 5-year PFS (0% vs. 88%, P = 0.016). CONCLUSION: The cellular composition of infused graft seems to impact on the hematologic recovery and PFS post-transplant. Further studies are needed to verify the optimal autograft cellular content in PCNSL.

Autograft cellular composition and outcome in NHL patients: results of the prospective multicenter GOA study.

Autologous stem cell transplantation (auto-SCT) is an established treatment option in patients with non-Hodgkin lymphoma (NHL). In this prospective multicenter study, the effect of infused blood graft cellular composition on post-transplant outcome was analyzed in 129 NHL patients. Higher graft CD34+ cell content (>2.5 × 106/kg) correlated with better progression-free survival (PFS) (p=.009) and overall survival (OS) (p=.004). Higher graft CD34+CD133+CD38- counts (>0.08 × 106/kg) were also linked with better PFS (p=.03) and OS (p=.004), and these survival benefits retained in multivariate analyses. Higher infused CD3+CD4+ cell count (>37 × 106/kg) predicted better PFS (p=.013) and OS (p=.007) in multivariate analysis. Autograft cellular composition seems to impact outcome in NHL patients. These observations regarding composition of optimal graft in autologous setting should be validated in an independent patient series or in a randomized study.

A prospective comparison of pegfilgrastim and lipegfilgrastim combined with chemotherapy in the mobilization of CD34+ cells in NHL patients.

BACKGROUND: Autologous stem cell transplantation (auto-SCT) is a treatment approach in non-Hodgkin lymphoma (NHL) patients. The options for mobilization of CD34+ cells to support high-dose therapy are granulocyte-colony stimulating factors (G-CSFs) alone or after chemotherapy. Limited data exist on the efficacy of lipegfilgrastim (LIPEG) in the mobilization field. PATIENTS AND METHODS: The present prospective nonrandomized study compared LIPEG 6 mg (n = 40) with pegfilgrastim (PEG) 6 mg (n = 37) in the mobilization of blood CD34+ cells after chemotherapy in NHL patients with comparable mobilizing chemotherapy and disease status before auto-SCT. RESULTS: Significantly higher blood CD34+ cell (B-CD34+ ) counts were observed in the LIPEG group at the start of the first apheresis (44 vs 23 × 106 /L, P = .009), in line with a higher collection yield of the first apheresis (3.3 vs 2.1 × 106 /kg, P = .086) and total yield of CD34+ cells (4.7 vs 2.9 × 106 /kg, P = .004). LIPEG proved to be a more effective G-CSF, resulting in a higher B-CD34+ cell peak (60 vs 32 × 106 /L, P = .030) and higher proportion of excellent mobilizers (33% vs 8%, P = .008). The superiority of LIPEG was confirmed in the multivarite analysis concerning the CD34+ cell yield of the first apheresis day (P = .010) and the total yield (P = .001). CONCLUSION: The mobilization of blood grafts with LIPEG added to chemotherapy was associated with higher CD34+ cell apheresis yields than with PEG. A randomized study is warranted to verify these findings.

CD34+ cell mobilization, blood graft composition, and posttransplant recovery in myeloma patients compared to non-Hodgkin's lymphoma patients: results of the prospective multicenter GOA study.

BACKGROUND: Autologous stem cell transplantation is an established treatment option for patients with multiple myeloma (MM) or non-Hodgkin's lymphoma (NHL). STUDY DESIGN AND METHODS: In this prospective multicenter study, 147 patients with MM were compared with 136 patients with NHL regarding the mobilization and apheresis of blood CD34+ cells, cellular composition of infused blood grafts, posttransplant recovery, and outcome. RESULTS: Multiple myeloma patients mobilized CD34+ cells more effectively (6.3 × 106 /kg vs. 3.9 × 106 /kg, p = 0.001). The proportion of poor mobilizers (peak blood CD34+ cell count <20 × 106 /L) was higher in NHL patients (15% vs. 3%, p < 0.001). Plerixafor was added to rescue the mobilization failure in 17 MM patients (12%) and in 35 NHL patients (26%; p = 0.002). The infused grafts contained more natural killer (NK) and CD19+ cells in MM patients. Blood platelet and NK-cell counts were higher in MM patients posttransplant. Early treatment-related mortality was low in both groups, but NHL patients had a higher late (>100 days) nonrelapse mortality (NRM; 6% vs. 0%, p = 0.003). CONCLUSIONS: Non-Hodgkin's lymphoma and MM patients differ in terms of mobilization of CD34+ cells, graft cellular composition, and posttransplant recovery. Thus, the optimal graft characteristics may also be different.

Importance of early immune recovery after autologous hematopoietic cell transplantation in lymphoma patients.

Lymphomas constitute the second most common indication for autologous hematopoietic cell transplantation (AHCT). Graft infusion is followed by a rapid hematological recovery and slower immune recovery. The number of natural killer cells and CD3+ T lymphocytes achieve normal counts usually within a month, whereas the recovery of CD3+CD4+ T lymphocytes is much slower. Early immune recovery is usually defined as the absolute lymphocyte count (ALC) ≥0.5 × 109/L, which has been associated with improved progression-free and even overall survival. Several factors have been associated with early immune recovery, including higher infused lymphocyte and CD34+ cell doses, both of which are affected by the choice of mobilization. This review summarizes the clinical importance of early immune recovery for long-term success of AHCT in lymphomas. Factors known to affect early immune recovery are discussed and suggestions made how to improve mobilization and collection processes to optimize immune recovery and post-transplant outcomes.

Blood graft composition and post-transplant recovery in myeloma patients mobilized with plerixafor: a prospective multicenter study.

The composition of autologous blood grafts after cryopreservation, post-transplant hematological recovery up to 1 year and immune recovery up to 6 months as well as outcome was analyzed in 87 patients with multiple myeloma (MM). The patients receiving added plerixafor due to poor mobilization (11%) were compared to those mobilized with G-CSF or cyclophosphamide (CY) plus G-CSF. The use of plerixafor was found to significantly affect the graft composition as there was a significantly higher proportion of the more primitive CD34+ cells, higher number of T and B lymphocytes as well as NK cells in the grafts of patients who received also plerixafor. The hematological recovery after auto-SCT was comparable between the groups. The recovery of CD3+CD4+ T cells was faster in plerixafor mobilized patients at 1 and 3 months post-transplant. There were no significant differences in progression-free (PFS) or overall survival (OS) according to the plerixafor use.

Impact of lenalidomide-based induction therapy on the mobilization of CD34+ cells, blood graft cellular composition, and post-transplant recovery in myeloma patients: a prospective multicenter study.

BACKGROUND: Lenalidomide is an immunomodulatory drug that is also currently used in transplant-eligible patients with multiple myeloma. Previous studies have suggested a negative impact of lenalidomide on the mobilization of CD34+ cells. No data are available regarding the more detailed composition of blood grafts after lenalidomide. STUDY DESIGN AND METHODS: In a multicenter, prospective study, we analyzed the mobilization of CD34+ cells, graft cellular composition, and post-transplant hematologic recovery in 26 patients with multiple myeloma after lenalidomide-based induction and in 34 lenalidomide-naive controls with multiple myeloma. All patients were mobilized with low-dose cyclophosphamide plus granulocyte-colony-stimulating factor. The cellular composition of the grafts was analyzed from thawed, cryopreserved samples with flow cytometry. Graft function was evaluated by engraftment data and by complete blood counts until 12 months after the graft infusion. RESULTS: Patients in the lenalidomide arm had lower median peak CD34+ counts and approximately 40% lower CD34+ cell yields from the first apheresis session, but these differences were not significant. The median total number of CD34+ cells collected was comparable (6.4 vs. 7.5 × 106 /kg). The number of apheresis sessions was higher in the lenalidomide group (2 vs. 1; p = 0.039). The blood graft composition was comparable between the groups. Hematologic recovery within 12 months post-transplant did not differ between the groups. CONCLUSION: Lenalidomide-based induction seems to have an impact on the number of aphereses performed, but not on the total yields of the CD34+ cells in the graft. Neither cellular composition of the grafts nor post-transplant recovery was affected by the limited pre-transplant exposure to lenalidomide.

Plerixafor injection: a hematopoietic stem cell mobilizer in non-Hodgkin lymphoma and multiple myeloma.

INTRODUCTION: A combination of granulocyte colony-stimulating factor (G-CSF) and chemotherapy or G-CSF alone are the most common mobilization regimens for autotransplantations. Plerixafor is used for mobilization of CD34(+) cells with G-CSF in non-Hodgkin lymphoma (NHL) and myeloma (MM) patients. AREAS COVERED: The available phase II and III data on plerixafor has been reviewed. The efficacy of plerixafor in the mobilization of CD34(+) cells in predicted poor mobilizers as well as in patients who had failed a mobilization has been evaluated. The pre-emptive use of plerixafor as well as studies on cost-effectiveness are covered. Also effects in the composition of the collected grafts along with the data on long-term outcome of plerixafor-mobilized patients is discussed. Expert commentary: Plerixafor combined with G-CSF mobilizes CD34(+) cells more efficiently than G-CSF alone in patients with NHL or MM. In phase III studies, engraftment after high-dose therapy has been comparable to G-CSF mobilized patients. The pre-emptive use of plerixafor added to mobilization with chemotherapy plus G-CSF or with G-CSF alone has gained more popularity. This approach may be more cost-effective than the routine use of this drug. The changes observed in the composition of grafts after plerixafor injection may have implications for post-transplant events.

Blood graft cellular composition and posttransplant outcomes in myeloma patients mobilized with or without low-dose cyclophosphamide: a randomized comparison.

BACKGROUND: Autologous stem cell transplantation is a standard treatment in multiple myeloma (MM). Blood grafts are usually collected after mobilization with granulocyte-colony-stimulating factor (G-CSF) alone or in a combination with cyclophosphamide (CY). There is limited knowledge of the possible effects of different mobilization regimens on blood graft characteristics and posttransplant outcomes. STUDY DESIGN AND METHODS: Thirty-eight patients with MM were included in this study. The patients were randomly assigned at registration to mobilization with either low-dose CY plus G-CSF (Arm A) or G-CSF alone (Arm B) and received three cycles of lenalidomide, bortetzomib, and dexamethasone induction. Flow cytometry analysis of lymphocyte subsets in the blood grafts after cryopreservation was performed. Hematologic and immune recovery were evaluated up to 12 months posttransplant. RESULTS: The blood grafts in Arm A contained significantly more CD34+ cells but in Arm B there was a greater proportion of CD34+CD38- cells and higher numbers of T and B lymphocytes as well as natural killer (NK) cells. The engraftment was comparable but lymphocyte count at 15 days posttransplant was higher in Arm B (0.8 × 10(9) /L vs. 0.5 × 10(9) /L, p = 0.033). At 3 and 6 months posttransplant the total number of NK cells was also higher in G-CSF-mobilized patients. There was no difference in progression-free survival between the study arms. CONCLUSION: CY plus G-GSF yields more CD34+ cells but seems to diminish lymphocyte and NK cell counts in the grafts and hampers immune recovery after transplantation. Thus G-CSF alone might be a preferred mobilization method due to more rapid immune recovery posttransplant.

Early immune recovery after autologous transplantation in non-Hodgkin lymphoma patients: predictive factors and clinical significance.

Limited data is available about the factors affecting early immune recovery or its clinical significance after autologous stem cell transplantation (auto-SCT). We prospectively analyzed factors affecting early immune recovery and outcome among 72 non-Hodgkin lymphoma (NHL) patients. Absolute lymphocyte count 15 d after auto-SCT (ALC-15) ≥ 0.5 × 10(9)/L was associated with the use of plerixafor (p = 0.004), the number of CD34(+) cells (p = 0.015), and CD34(+) CD38(-) cells (p = 0.005) in the grafts. ALC-15 ≥ 0.5 × 10(9)/L was associated with improved overall survival (p = 0.021). In patients with aggressive histology, ALC-15 ≥ 0.5 × 10(9)/L was beneficial in regard to both progression-free survival (p = 0.015) and overall survival (p = 0.002). Early immune recovery seems to be important in transplanted patients with NHL and, therefore, an easy and affordable method for disease-related risk analysis. Patients with aggressive histology and slow immune recovery may need additional post-transplant treatment.

Blood graft cellular composition and posttransplant recovery in non-Hodgkin's lymphoma patients mobilized with or without plerixafor: a prospective comparison.

BACKGROUND: Autologous stem cell transplantation is commonly used to treat non-Hodgkin's lymphomas (NHLs). Cellular composition of the blood grafts apparently has a role in the posttransplant hematologic and immune recovery. Plerixafor increases the mobilization of CD34+ cells and higher amounts of various lymphocyte subsets have been reported in the grafts. Limited prospective data are available in regard to graft cellular composition, hematologic and immune recovery, and patient outcomes in NHL patients who receive plerixafor added to chemomobilization. STUDY DESIGN AND METHODS: Forty-one patients with NHL participated in this prospective study. All patients received chemomobilization and 15 poor mobilizers also received plerixafor. CD34+ cell subsets and lymphocyte subsets of cell grafts, posttransplant hematologic and immune recovery, and outcome were evaluated. RESULTS: Blood grafts in the plerixafor group contained a significantly higher proportion of CD34+133+CD38- cells and more lymphocytes of all major subsets except B lymphocytes. Neutrophil engraftment was comparable and platelet recovery slightly slower in the plerixafor group. Natural killer cell recovery was significantly faster in patients mobilized with plerixafor. Otherwise hematologic and immune recovery as well as short-time outcome were comparable even though there was a trend for progression-free survival and overall survival benefit in the plerixafor group. CONCLUSIONS: In poorly mobilizing NHL patients, plerixafor added to chemomobilization is safe and effective. It also modifies the blood graft composition in many ways, some of which have been linked to better outcomes in previous studies. Larger sets of patients and longer follow-up are needed to see whether plerixafor-mobilized grafts are associated with superior outcome of the patients.