Autologous progenitor cell transplantation: prior exposure to stem cell- toxic drugs determines yield and engraftment of peripheral blood progenitor cell but not of bone marrow grafts

Agents with stem cell-toxic potential are frequently used for salvage therapy of Hodgkin's disease (HD) and high-grade non-Hodgkin's lymphoma (NHL). Because many patients with relapsed or refractory lymphoma are candidates for autologous progenitor cell transplantation, possible toxic effects of salvage chemotherapy on progenitor cells must be taken into account. In a retrospective study, we have analyzed the influence of a salvage regimen containing the stem cell-toxic drugs BCNU and melphalan (Dexa-BEAM) on subsequently harvested bone marrow (BM)- and peripheral blood-derived progenitor cell grafts (PBPC) and compared it with other factors. Progenitor cells were collected from 96 patients with HD or high-grade NHL. Seventy-nine grafts were reinfused (35 PBPC and 44 BM) after high-dose chemotherapy. Compared with patients autografted with BM, hematopoietic recovery was significantly accelerated in recipients of PBPC. For PBPC, the number of Dexa-BEAM cycles ( > or = v > 1) was the predominate prognostic factor affecting colony-forming unit-granulocyte-macrophage (CFU-GM) yield (66 v 6.8 x 10(4)/kg, P = .0001), CD34+ cell yield (6.6 v 1.6 x 10(6)/kg, P = .0001), neutrophil recovery to > 0.5 x 10(9)/L (9 v. 11 days, P = .0086), platelet recovery to > 20 x 10(9)/L (10 v 15.5 days, P = .0002), and platelet count on day +100 after transplantation (190 v 107 x 10(9)/L, P = .031) using univariate analysis. Previous radiotherapy was associated with significantly lower CFU-GM and CD34+ cell yields but had no influence on engraftment. Patient age, patient sex, disease activity, or chemotherapy other than Dexa-BEAM did not have any prognostic impact. Multivariate analysis confirmed that Dexa-BEAM chemotherapy was the overriding factor adversely influencing CFU-GM yield (P < .0001), CD34+ cell yield (P < .0001), and platelet engraftment (P < .0001). BM grafts were not significantly affected by previous Dexa-BEAM chemotherapy or any other variable tested. However, prognostic factors favoring the use of BM instead of PBPC were not identified using joint regression models involving interaction terms between the graft type (PBPC or BM) and the explanatory variables investigated. We conclude that, in contrast to previous radiotherapy or other chemotherapy, exposure to salvage regimens containing stem cell- toxic drugs, such as BCNU and melphalan, is a critical factor adversely affecting yields and performance of PBPC grafts. Marrow progenitor cells appear to be less sensitive to stem cell-toxic chemotherapy. PBPC should be harvested before repeated courses of salvage chemotherapy involving stem cell-toxic drugs to preserve the favorable repopulation kinetics of PBPC in comparison with BM.     

VACOP-B, high-dose cyclophosphamide and high-dose therapy with peripheral blood progenitor cell rescue for aggressive non-Hodgkin's lymphoma with bone marrow involvement: a study by the non-Hodgkin's Lymphoma Co-operative Study Group

BACKGROUND AND OBJECTIVE: Sequential treatment with the addition of high-dose therapy (HDT) and peripheral blood progenitor cell (PBPC) rescue has been reported to be active as front-line therapy in aggressive non-Hodgkin's lymphoma (NHL) with bone marrow (BM) involvement. We designed an intensive sequential therapy as front-line therapy in this subset of patients and conducted a phase II study. DESIGN AND METHODS: Patients with aggressive non-Hodgkin's lymphoma and BM involvement at diagnosis received 8 weeks of VACOP-B chemotherapy as induction therapy. The second phase included high-dose cyclophosphamide (HDCY) (7 g/m(2)) with granulocyte colony-stimulating factor (G-CSF) followed by leukaphereses. The third phase included HDT according to the BEAM protocol or melphalan (140 mg/m(2)) plus total body irradiation (8 Gy in a single dose). RESULTS: Forty patients were included in the study. According to the intention-to-treat, after VACOP-B, 11 (27.5%) and 22 (55%) patients achieved complete remission (CR) and partial remission (PR), respectively. Thirty-four received HDCY. After HDCY, 18 patients (45%) were in CR and 13 (32.5%) in PR. Twenty-nine underwent HDT plus peripheral blood cell rescue (PBPC) rescue. At the completion of treatment 29 patients (72.5%) were in CR, and 3 patients (7.5%) in PR. The actuarial 3-year overall survival, disease free survival and failure free survival are 48%, 55% and 40%, respectively. Overall severe toxicity was 7.5%. INTERPRETATION AND CONCLUSIONS: This phase II study suggests that the intensified treatment described is feasible and active in aggressive NHL with BM involvement. A randomized trial is now underway to test this approach.     

Comparative effects of granulocyte-macrophage colony-stimulating factor (GM-CSF) and granulocyte colony-stimulating factor (G-CSF) on priming peripheral blood progenitor cells for use with autologous bone marrow after high-dose chemotherapy

Two hematopoietic colony-stimulating factors, granulocyte colony- stimulating factor (G-CSF) and granulocyte-macrophage CSF (GM-CSF), have been shown to accelerate leukocyte and neutrophil recovery after high-dose chemotherapy and autologous bone marrow (BM) support. Despite their use, a prolonged period of absolute leukopenia persists during which infections and other complications of transplantation occur. We collected large numbers of peripheral blood (PB) progenitors after CSF administration using either G-CSF or GM-CSF and tested their ability to affect hematopoietic reconstitution and resource utilization in patients undergoing high-dose chemotherapy and autologous BM support. Patients with breast cancer or melanoma undergoing high-dose chemotherapy and autologous BM support were studied in sequential nonrandomized trials. After identical high-dose chemotherapy, patients received either BM alone, with no CSF; BM with either G-CSF or GM-CSF; or BM with G-CSF or GM-CSF and G-CSF or GM-CSF primed peripheral blood progenitor cells (PBPC). Hematopoietic reconstitution, as well as resource utilization, was monitored in these patients. The use of CSF- primed PBPC led to a highly significant reduction in the duration of leukopenia with a white blood cell (WBC) count under 100 and 200 cells/mL, and neutrophil count under 100 and 200 cells/mL with both GM- and G-CSF primed PB progenitor cells, compared with the use of the CSF with BM or with historical controls using BM alone. In addition, the use of CSF-primed PBPC resulted in a significant reduction in median number of antibiotics used, days in the Bone Marrow Transplant Unit, and hospital resources used. Patients receiving G-CSF primed PBPC also experienced a reduction in the median number of days in the hospital, red blood cell (RBC) transfusions, platelet transfusions, days on antibiotics, and discounted hospital charges. Phenotypic analysis of the CSF-primed PBPC indicated the presence of cells bearing antigens associated with both early and late hematopoietic progenitor cells. The use of CSF-primed PBPC can significantly improve hematopoietic recovery after high-dose chemotherapy and autologous BM support. In addition, the use of G-CSF-primed PBPC was associated with a significant reduction in hospital resource utilization, and a reduction in hospital charges.     

Intensive therapy with peripheral blood progenitor cell transplantation in 60 patients with poor-prognosis follicular lymphoma

Intensive therapy, mainly with purged autologous bone marrow transplantation (ABMT), has been proposed in recent years as consolidation treatment in young patients with follicular lymphoma. Reported experience with transplantation of peripheral blood progenitor cells (PBPC) is, so far, limited. The feasibility and the therapeutic efficacy of intensive therapy followed by unpurged autologous PBPC reinfusion were evaluated in 60 patients with poor-prognosis follicular lymphoma. Twelve patients were in first partial remission (PR), 34 were in second partial or complete remission (CR), and 14 were in subsequent progression. At the time of the procedure, 39 patients (65%) had persistent bone marrow involvement, 49 patients (82%) were in PR, and 16 patients had presented with a histologic transformation (HT). PBPC were collected after chemotherapy followed by granulocyte (G) colony- stimulating factor (CSF) or granulocyte-macrophage (GM)-CSF in 50 patients. Conditioning regimens included high-dose chemotherapy alone (14 patients); mainly the BCNU, etoposide, aracytine, melphalan [BEAM] regimen), or cyclophosphamide with or without etoposide plus total body irradiation (46 patients). The median time to reach a neutrophil count greater than 0.5 x 10(9)/L was 13 days. There were five treatment- related deaths, with four being associated with a delayed engraftment and all occurring in patients in third or subsequent progression. At a median follow-up of 21 months, 48 patients were still alive, 18 relapsed, and seven died of lymphomas progression. Estimated 2-year overall survival (OS) and failure-free survival (FFS) rates were 86% and 53%, respectively, without or plateau. Patients treated in PR1 or PR2/CR2 had a significantly longer rate of OS and FFS than those treated in subsequent progression (P = .002 and P = .001, respectively), whereas age, response to salvage treatment, presence or absence of residual bone marrow involvement, or conditioning regimen had no influence on outcome. Patients with HT tended to have a worse FFS rate (P = .04) without an OS difference. Along with an unusual rate of engraftment failure, the poor FFS observed in heavily pretreated patients suggests that intensive therapy should be performed early in the course of the disease. Given the high percentage of patients intensified in PR with residual bone marrow involvement, our results are comparable with those achieved with ABMT published to date. Prospective trials are warranted to compare this strategy with standard therapy in patients with relapsing or PR follicular lymphoma.     

Infused CD34 cell dose, but not tumour cell content of peripheral blood progenitor cell grafts, predicts clinical outcome in patients with diffuse large B-cell lymphoma and follicular lymphoma grade 3 treated with high-dose therapy

Previously, we have shown that patients with diffuse large B-cell lymphoma (DLBCL) transplanted with contaminated bone marrow (BM) generally have a poor outcome. Whether this is also the case when peripheral blood progenitor cell (PBPC) grafts are used is not known. Forty-three patients with chemosensitive DLBCL or follicular lymphoma grade 3 (FLgr3) were treated with high-dose therapy (HDT) and autologous stem cell support. Nine patients received purged grafts. Quantitative real-time polymerase chain reaction (QRT-PCR) for either the BCL2/IgH translocation or allele specific oligonucleotide (ASO) QRT-PCR for the immunoglobulin heavy chain (IgH) complementarity-determining region 3 were used. Nine of 25 (36%) PBPC grafts contained tumour cells as tested by QRT-PCR, including two grafts purged by CD34(+) cell enrichment combined with B-cell depletion. The level of contamination of the PBPC/CD34(+) cells ranged from 0 to 8.28%. No relationship could be shown between the total number of tumour cells infused and relapse. Patients receiving PCR-positive or PCR-negative PBPC grafts had similar progression-free survival (PFS) (P = 0.49). However, a significant difference was seen in PFS and overall survival (OS) for the patients given >/=6.1 x 10(6) CD34(+) cells/kg compared with those given <6.1 x 10(6) CD34(+) cells/kg (P = 0.01 and P < 0.05 respectively).     

Peripheral blood progenitor cells mobilized by recombinant human granulocyte colony-stimulating factor plus recombinant rat stem cell factor contain long-term engrafting cells capable of cellular proliferation for more than two years as shown by serial transplantation in mice

Mobilized peripheral blood progenitor cells (PBPC) have been shown to provide rapid engraftment in patients given high-dose chemotherapy. PBPC contain cells with long-term engraftment potential as shown in animal models. In this study we have further analyzed mobilized PBPC for their ability to support serial transplantation of irradiated mice. Transplantation of recombinant human granulocyte colony-stimulating factor (rhG-CSF) plus recombinant rat stem cell factor (rrSCF) mobilized PBPC resulted in 98% donor engraftment of primary recipients at 12 to 14 months post-transplantation. Bone marrow (BM) cells from these primary recipients were harvested and transplanted into secondary recipients. At 6 months posttransplantation, all surviving secondary recipients had donor engraftment. Polymerase chain reaction (PCR) analysis showed greater than 90% male cells in spleens, thymuses, and lymph nodes. Myeloid colonies from BM cells of secondary recipients demonstrated granulocyte/macrophage colony-forming cells (GM-CFC) of male origin in all animals. In comparison, transplantation of rhG-CSF mobilized PBPC resulted in decreased male engraftment in secondary recipients. BM cells from secondary recipients, who originally received PBPC mobilized by the combination of rrSCF and rhG-CSF, were further passaged to tertiary female recipients. At 6 months posttransplantation, 90% of animals had male-derived hematopoiesis by whole-blood PCR analysis. These data showed that PBPC mobilized with rhG-CSF plus rrSCF contained cells that are transplantable and able to maintain hematopoiesis for more than 26 months, suggesting that the mobilized long-term reconstituting stem cells (LTRC) have extensive proliferative potential and resemble those that reside in the BM. In addition, the data demonstrated increased mobilization of LTRC with rhG- CSF plus rrSCF compared to rhG-CSF alone.     

An analysis of engraftment kinetics as a function of the CD34 content of peripheral blood progenitor cell collections in 692 patients after the administration of myeloablative chemotherapy

The CD34 antigen is expressed by committed and uncommitted hematopoietic progenitor cells and is increasingly used to assess stem cell content of peripheral blood progenitor cell (PBPC) collections. Quantitative CD34 expression in PBPC collections has been suggested to correlate with engraftment kinetics of PBPCs infused after myeloablative therapy. We analyzed the engraftment kinetics as a function of CD34 content in 692 patients treated with high-dose chemotherapy (HDC). Patients had PBPCs collected after cyclophosphamide based mobilization chemotherapy with or without recombinant human granulocyte colony-stimulating factor (rhG-CSF) until > or = 2.5 x 10(6) CD34+ cells/kg were harvested. Measurement of the CD34 content of PBPC collections was performed daily by a central reference laboratory using a single technique of CD34 analysis. Forty-five patients required a second mobilization procedure to achieve > or = 2.5 x 10(6) CD34+ cells/kg and 15 patients with less than 2.5 x 10(6) CD34+ cells/kg available for infusion received HDC. A median of 9.94 x 10(6) CD34+ cells/kg (range, 0.5 to 112.6 x 10(6) CD34+ cells/kg) contained in the PBPC collections was subsequently infused into patients after the administration of HDC. Engraftment was rapid with patients requiring a median of 9 days (range, 5 to 38 days) to achieve a neutrophil count of 0.5 x 10(9)/L and a median of 9 days (range, 4 to 53+ days) to achieve a platelet count of > or = 20 x 10(9)/L. A clear dose-response relationship was evident between the number of CD34+ cells per kilogram infused between the number of CD34+ cells per kilogram infused and neutrophil and platelet engraftment kinetics. Factors potentially influencing the engraftment kinetics of neutrophil and platelet recovery were examined using a Cox regression model. The single most powerful mediator of both platelet (P = .0001) and neutrophil (P = .0001) recovery was the CD34 content of the PBPC product. Administration of a post-PBPC infusion myeloid growth factor was also highly correlated with neutrophil recovery (P = .0001). Patients receiving high-dose cyclophosphamide, thiotepa, and carboplatin had more rapid platelet recovery than patients receiving other regimens (P = .006), and patients requiring 2 mobilization procedures versus 1 mobilization procedure to achieve > or = 2.5 x 10(6) CD34+ cells/kg experienced slower platelet recovery (P = .005). Although a minimal threshold CD34 dose could not be defined, > or = 5.0 x 10(6) CD34+ cells/kg appears to be optimal for ensuring rapid neutrophil and platelet recovery.     

Significance of detection of occult non-Hodgkin's lymphoma in histologically uninvolved bone marrow by a culture technique.

Prolonged disease-free survival of patients with recurrent or resistant non-Hodgkin's lymphoma (NHL) has been achieved with high-dose therapy followed by autologous bone marrow transplantation (ABMT). A concern with the use of ABMT is that the marrow that is reinfused may contain undetected NHL cells with the potential to reestablish metastatic disease in the recipient. Using a culture technique that is sensitive for detecting occult lymphoma cells in BM, we analyzed histologically normal marrow harvests from 59 consecutive patients with intermediate- or high-grade NHL who were candidates for high-dose therapy and ABMT. The culture results indicated that 22 of the patients had occult lymphoma in their marrow. Forty-three patients underwent high-dose therapy followed by ABMT. Twenty-four achieved a complete clinical remission. Those with occult lymphoma in their harvests (11 patients) continued to relapse for up to 3 years, whereas no relapses were observed beyond 8 months in 13 patients receiving marrow that did not contain detectable lymphoma cells using the culture technique. The relapses in the patients who achieved a complete remission occurred at sites of prior bulky disease rather than at new sites, suggesting that the ability to detect occult lymphoma cells in marrow is a marker of biologic aggressiveness and/or resistance to therapy, or that the reinfused cells could only grow in previously involved sites. The detection of lymphoma cells in marrow used for ABMT is an important adverse prognostic factor, and appears to be independent of other clinical predictors of outcome such as sensitivity or resistance of disease to prior chemotherapy.     

Molecular analysis of patients with relapsed or refractory intermediate-high grade non-Hodgkin's lymphoma with bone marrow infiltration undergoing peripheral blood progenitor cell transplantation.

BACKGROUND AND OBJECTIVES: IgH gene rearrangement studies with a polymerase chain reaction (PCR) technique can detect the persistence of clonal cells at molecular level during the remission phase. This persistence of clonal cells can be used to establish the relationship between minimal residual disease (MRD) and clinical outcome. We have developed a three-step single strand conformational polymorphism PCR strategy which is able to detect clonal B lymphoid cells at a frequency as low as 1 clonal cell in 10(6) normal cells. DESIGN AND METHODS: Twenty patients with intermediate or high-grade B non-Hodgkin's lymphoma (NHL) were evaluated. Patients were pre-treated with a median of two (range 1-4) conventional chemotherapy lines before high-dose cyclophosphamide (HDCY). All patients had their bone marrow (BM) involved by disease (median 10%; range 5-50%). Nineteen patients were offered high-dose therapy followed by peripheral blood progenitor cells (PBPC) autografting. RESULTS: MRD analysis was performed for each patient at the end of conventional chemotherapy and every three months after high dose therapy. All these patients achieved complete response (CR) after high dose therapy (HDT). Six patients relapsed after a median time of 24.5 months. All the studied apheresis samples were positive at the molecular analysis. All 6 patients still positive at the molecular analysis after PBPC autografting relapsed. The remaining 13 patients who were negative maintained CR. INTERPRETATION AND CONCLUSIONS: Whereas the detection of clonal cells in the apheresis samples did not predict an unfavorable outcome, the disappearance of the clonal rearranged band from the BM sample after HDT proved to be a favorable prognostic factor and was associated with long-lasting disease-free status     

Durable remissions with autologous stem cell transplantation for high-risk HIV-associated lymphomas

The treatment of HIV-associated lymphoma has changed since the widespread use of highly active antiretroviral therapy. HIV-infected individuals can tolerate more intensive chemotherapy, as they have better hematologic reserves and fewer infections. This has led to higher response rates in patients with HIV-associated Hodgkin disease (HD) or non-Hodgkin lymphoma (NHL) treated with chemotherapy in conjunction with antiretroviral therapy. However, for patients with refractory or relapsed disease, salvage chemotherapy still offers little chance of long-term survival. In the non-HIV setting, patients with relapsed Hodgkin disease (HD) or non-Hodgkin lymphoma (NHL) have a better chance of long-term remission with high-dose chemotherapy with autologous stem cell rescue (ASCT) compared with conventional salvage chemotherapy. In a prior report we demonstrated that this approach is well tolerated in patients with underlying immunodeficiency from HIV infection. Furthermore, similar engraftment to the non-HIV setting and low infectious risks have been observed. Herein, we expand upon this early experience with the largest single institution series of 20 patients. With long-term follow-up we demonstrate that ASCT can lead to an 85% progression-free survival, which suggests that this approach may be potentially curative in select patients with relapsed HIV-associated HD or NHL.     

Mobilization of peripheral blood progenitor cells (PBPC) in patients undergoing chemotherapy followed by autologous peripheral blood stem cell transplant (SCT) for high risk breast cancer (HRBC).

We have determined the effect of delayed addition of G-CSF after chemotherapy on PBPC mobilization in a group of 30 patients with high risk breast cancer (HRBC) undergoing standard chemotherapy followed by high-dose chemotherapy (HDCT) and autologous SCT. Patients received FAC chemotherapy every 21 days followed by G-CSF at doses of 5 microg/kg/day starting on day +15 (groups 1 and 2) or +8 (group 3) after chemotherapy. PBPC collections were performed daily starting after 4 doses of G-CSF and continued until more than 2.5 x 10(6) CD34+ cells had been collected. In group 1, steady-state BM progenitors were also harvested and used for SCT. Groups 2 and 3 received PBPC only. The median number of collections was three in each group. Significantly more PB CD34+ cells were collected in patients receiving G-CSF starting on day 8 vs day 15 (9.43 x 10(6)/kg and 6.2 x 10(6)/kg, respectively) (P < 0.05). After conditioning chemotherapy all harvested cells including BM and PBPC were reinfused. Neutrophil and platelet engraftment was significantly faster in patients transplanted with day 8 G-CSF-mobilized PBPC (P < 0.05) and was associated with lower transplant related morbidity as reflected by days of fever, antibiotics or hospitalization (P < 0.05). Both schedules of mobilization provided successful long-term engraftment with 1 year post-transplant counts above 80% of pretransplant values. In conclusion, we demonstrate that delayed addition of G-CSF results in successful mobilization and collection of PBPC with significant advantage of day 8 G-CSF vs day 15. PBPC collections can be scheduled on a fixed day instead of being guided by the PB counts which provides a practical advantage. Transplantation of such progenitors results in rapid short-term and long-term trilineage engraftment.     

Ex-vivo expansion of hematopoietic progenitor cells: preliminary results in breast cancer

Ex-vivo expanded progenitor cells have been proposed as a source of cells to support high-dose chemotherapy and to decrease or eliminate the period of neutropenia following transplantation. To date, no clinical studies using ex vivo expanded cells, have demonstrated any decrease in the time to neutrophil or platelet recovery, although a number of clinical studies have been performed using a variety of growth factor cocktails and culture conditions. Over the past 6 years we have developed a static culture system that results in optimal expansion of myeloid progenitor cells. We have initiated a clinical study to evaluate this culture system in breast cancer patients receiving peripheral blood progenitor cells (PBPC) to support high-dose chemotherapy. CD34 selected cells were cultured for 10 days in 800 ml of defined media (Amgen Inc.) containing 100 ng/ml each of rhSCF, rhG-CSF and rhMGDF in 1L teflon bags (American Fluoroseal) at 20,000 to 50,000 cells per ml. After culture the cells were washed with 3 volumes of PBS to remove all media and growth factors and reinfused on day 0 of transplant followed by daily administration of rhG-CSF. On day +1 the patients received an unexpanded PBPC product to ensure the durability of the graft. Patients transplanted with expanded PBPC cells recovered neutrophil counts (ANC > 500/microl) as early as day 4 post transplant with a median of 6 days (range 4 to 14 days). In comparison, our historical control group of patients (N=175) had a median time to neutrophil engraftment of 9 days (range 7 to 24 days). A second cohort of patients were transplanted with expanded cells alone and a similar rapid engraftment was obtained. The first patients are now over 70 days post transplant with durable engraftment. No effect on platelet recovery has been observed in any patients to date. These data demonstrate that PBPC expanded under the conditions defined can significantly shorten the time to engraftment of neutrophils.     

Autologous bone marrow versus non-mobilized peripheral blood stem cell transplantation for lymphoid malignancies: A prospective,comparative trial

Autologous transplantation using bone marrow stem cells (BMSC) or peripheral blood stem cells (PBSC) is widely used for non-Hodgkin's lymphoma (NHL) and Hodgkin's disease (HD). We report a randomized, comparative trial comparing BMSC vs. nonmobilized PBSC for responsive NHL or HD. Patients randomized to BMSC (n = 13) vs. PBSC (n = 15) had more rapid neutrophil recovery (median 23 vs. 30 days), RBC independence (25 vs. 62 days), platelet independence (24 vs. 54 days), and shorter hospital stay. However, neither relapse, overall survival, nor relapse-free survival were different receiving BMSC vs. PBSC (all P > .7). Concurrently, 54 others (34 BMSC, 20 PBSC) were assigned non-randomly because of resistant disease or marrow unsuitable for harvest and similar patterns of engraftment favoring BMSC over PBSC were observed. In the entire group, BMSC transplantation (n = 47) led to quicker neutrophil recovery (P = .02), RBC (P = .06), and platelet independence (P = .04) and earlier hospital discharge (P = .02) vs. PBSC (n = 35). No difference in relapse, overall, or relapse-free survival were observed using BMSC vs. PBSC. These data suggest that non-mobilized PBSC are a satisfactory alternative to BMSC in patients with unsuitable marrow; however, transplantation with non-mobilized PBSC was associated with slower hematologic recovery, and longer hospital stay. No difference in tumor recurrence rates was observed between the PBSC or BMSC recipients. Unprimed PBSC transplantation offered no clinical advantage to BMSC. Am. J. Hematol. 54:202–208, 1997 © Wiley-Liss, Inc.     

Long-term follow-up of a phase III study of recombinant human granulocyte-macrophage colony-stimulating factor after autologous bone marrow transplantation for lymphoid malignancies

One hundred and twenty-eight patients with non-Hodgkin's lymphoma (NHL), Hodgkin's disease (HD), and acute lymphoblastic leukemia (ALL) previously reported from a phase III trial of rhGM-CSF or placebo following autologous bone marrow transplantation (ABMT) were investigated for the development of late toxicities. Median follow-up is 36 months. No apparent long-term deleterious effects on BM function were observed. Moreover, disease-free survival and overall survival were similar for patients on both treatment arms, arguing for the long- term safety of recombinant human granulocyte macrophage-colony- stimulating factor (rhGM-CSF). The only factors predictive for both a high risk of relapse over time and mortality were having the diagnosis of ALL and/or undergoing ABMT in resistant relapse. We attempted to identify clinical variables before BM harvest, at the time of marrow infusion, or events within the first 100 days posttransplant, which might predict speed of neutrophil recovery in the setting of placebo or rhGM-CSF administration after ABMT. Only previous exposure to agents that deplete stem cells led to a significant delay in neutrophil recovery, suggesting their avoidance in patients who may undergo ABMT. Nevertheless, even those patients benefited from rhGM-CSF. For all patients, rhGM-CSF and agents that deplete stem cells were the strongest independent predictors for neutrophil engraftment. With the increasing use of newer hematopoietic growth factors both alone and in combination, long-term follow-up is essential to confirm the same safety that we report with rhGM-CSF.     

A phase II study of continuous infusion recombinant human granulocyte- macrophage colony-stimulating factor as an adjunct to autologous bone marrow transplantation for patients with non-Hodgkin's lymphoma in first remission

Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) clearly hastens myeloid recovery in patients with relapsed hematologic malignancies undergoing autologous bone marrow transplantation (ABMT). In efforts to further improve neutrophil engraftment and shorten hospital stay in ABMT patients, rhGM-CSF was administered by a potentially more potent route (continuous infusion) to non-Hodgkin's lymphoma (NHL) patients with better BM reserve (first remission). Time to myeloid engraftment was compared with that of NHL patients treated in first remission at our institution on a similar ABMT protocol but without growth factor support (controls). Median neutrophil engraftment (absolute neutrophil count, 500 cells/microL) in first remission patients treated with rhGM-CSF was 14 days, compared with 22 days in controls (P = .0001). Hospital stays were also significantly reduced for rhGM-CSF patients (P = .0003). Platelet engraftment did not differ between the two groups. Persistent fever and generalized serositis were the primary toxicities. rhGM-CSF, delivered by this route, was efficacious but more toxic than 2-hour rhGM-CSF infusions previously reported by other investigators. Future alterations in both dose and schedule may retain comparable efficacy yet diminish toxicity.     

Molecular detection of clonally rearranged cells in peripheral blood progenitor cell harvests from multiple myeloma patients

Summary. Peripheral blood progenitor cells (PBPC) are increasingly used for autologous reconstitution following high-dose chemotherapy in multiple myeloma but it is unclear whether these cells are less likely to be contaminated with malignant cells than bone marrow (BM). We have investigated this using immunoglobulin heavy-chain (IgH) gene fingerprinting, a polymerase chain reaction based technique with a sensitivity of 0.1–0.01% (10^-3 - 10^-4). We have looked for patient-specific IgH rearrangements in leukapheresis samples from eight myeloma patients undergoing PBPC harvest. Seven were in first remission (six partial, one complete) and one in second complete remission. Mobilization of PBPC was accomplished using cyclophosphamide (4 or 7 mg/m²) and rhG- or GM-CSF. Between two and five leukaphereses were performed in each patient. Patient-specific IgH rearrangements were identified in diagnostic BM in all patients and bands of identical size were found in one or more leukaphereses from 6/8 patients. Overall, 14/32 leukaphereses were shown to be contaminated. Two patients who showed contamination of at least one PBPC harvest had BM harvests in which contaminating cells were not detectable, suggesting that PBPC are not necessarily less likely to be contaminated than marrow stem cells.
These results indicate that PBPC harvests from the majority of myeloma patients are likely to contain contaminating cells. Further studies are needed to determine whether these cells are clonogenic and whether they contribute to relapse.     

Long-term haematological reconstitution following BEAM and autologous transplantation of circulating progenitor cells in non-Hodgkin's lymphoma

We report on long-term haematological recovery and clinical outcome after high-dose chemotherapy supported by circulating progenitor cells (CPC) transplantation in non-Hodgkin's lymphoma (NHL) patients, and analyse the role of variables which might influence engraftment. 63 consecutive NHL patients were enrolled in this study. Two groups of patients were considered for analysis: the first 34 patients had untreated diffuse large cell lymphoma with unfavourable prognostic factors. A second group of 29 patients underwent transplantation for resistant or relapsing NHL with low, intermediate and high grade histology. All patients received the BEAM conditioning regimen. As already reported in many studies, all patients showed a rapid haematological reconstitution. 43 patients (68%) achieved long-term complete trilineage engraftment within a median of 107 d from CPC transplantation. The neutrophil count was the first parameter reaching complete normalization, and haemoglobin was the last. Failure to meet the trilineage levels was due to lack of platelet recovery and was more frequent in patients transplanted in the setting of salvage protocols. By Kaplan-Meier analysis, the probability of a full reconstitution was 80% in patients to whom transplant was offered as part of a front-line therapy and 50% when transplant was given in the salvage programmes. Multivariate analysis showed that sustained long-term haematological reconstitution was significantly related to younger age, the time taken to achieve short-term reconstitution, and bone marrow involvement.     

Peripheral blood progenitor cell transplantation in lymphoma and leukemia using a single apheresis

Myeloablative treatment and peripheral blood progenitor cell (PBPC) transplantation are increasingly used for lymphomas and leukemias. We have sought to optimize conditions for priming, collection, and engraftment of the leukapheresis product. Fifty-four consecutive adult patients were eligible, 31 with high-grade non-Hodgkin's lymphoma of poor prognosis, 12 with Hodgkin's disease in chemosensitive relapse, and 11 with poor prognosis acute lymphoblastic leukemia. Filgrastim was administered after routine chemotherapy with VAPEC-B or HiCCOM to mobilize PBPC. A rapidly increasing white blood cell count was used to predict the time of peak PBPC release and plan leukapheresis. Forty- five patients underwent leukapheresis. A median of 14 L of blood was processed at a single apheresis. A median of 2.4 x 10(8)/kg mononuclear cells (MNCs), 1.04 x 10(6)/kg granulocyte-macrophage colony-forming cells (GM-CFCs), and 10.6 x 10(6)/kg CD34+ cells were obtained. Slightly fewer MNCs were obtained from the heavily pretreated Hodgkin's disease group. There were no other significant differences in the size or composition of the leukapheresis harvest in the three patient groups. Forty patients underwent high-dose therapy and PBPC transplantation. Filgrastim was administered by daily subcutaneous injection until the absolute neutrophil count was > or = 1 x 10(9)/L for 2 consecutive days. Rapid and sustained hematopoietic engraftment occurred in all patients. The median time to achieve a neutrophil count > or = 0.5 x 10(9)/L was 9 days (range, 8 to 16 days); to achieve a platelet count > or = 20 x 10(9)/L was 10 days (range, 6 to 88 days); and to achieve a platelet count > or = 50 x 10(9)/L was 15.5 days (range, 10 to 100 days). Neutrophil recovery was faster than that of a historical control group treated with autologous bone marrow transplantation and filgrastim, but platelet recovery times were halved in the PBPC group. There was no secondary engraftment failure. Requirements for blood and platelet transfusions, antibiotic use, and parenteral nutrition were similar in the three patient groups. The median number of days in the hospital was 13 (range, 10 to 55) in the PBPC patients, compared with 19 (range, 14 to 51) in the historical controls. Leukapheresis yields (MNC, GM-CFC, and CD34+ cell numbers) were not useful for predicting the times to engraftment. We have shown that sufficient PBPC for transplantation can be obtained at a single leukapheresis after mobilization with routine chemotherapy and filgrastim in patients with non-Hodgkin's lymphoma, Hodgkin's disease, and acute lymphoblastic leukemia, even those heavily pretreated.(ABSTRACT TRUNCATED AT 400 WORDS)     

Side population cells in highly enriched CD34-positive cells from peripheral blood progenitor cells identify an immature subtype of hematopoietic progenitor cells but do not predict time to engraftment in patients treated with high-dose therapy

Objective: A Hoechst 33342 dye efflux assay can be used to define a population of immature hematopoietic progenitor cells (HPC) that are called side population (SP) cells. Previously, SP cells examined from bone marrow (BM) and peripheral blood progenitor cells (PBPC) were found to be predominantly CD34 negative. Methods and results: In this study, we show that the level of CD34+ cells within the SP fraction increases from 2% in BM to 15% in mobilized PBPC. Furthermore, SP cells are found in highly enriched CD34+ cells from both BM and PBPC, and these cells define an immature phenotype of HPC. We also observed a higher level of CD133+ cells within the SPCD34+ cell population. Moreover, the frequency of long‐term culture‐initiating cells (LTC‐IC) was markedly increased in SPCD34+ cells. To further investigate whether variations in the level of SP cells in the CD34+ cell fraction influenced short‐term engraftment, we studied 20 patients with Hodgkin lymphoma that were autotransplanted with highly enriched CD34+ cells from PB. The percentage of SP cells in the PBCD34+ cell fraction was highly variable, ranging from 0.3 to 22%. No correlation was found between the content of SP cells in the autotransplanted CD34+ cells and time to short‐term engraftment. Conclusion: SPCD34+ cells in PBPC define an immature phenotype of HPC with increased numbers of LTC‐IC, and they are more frequently found in PBPC than in BM. The number of SP cells does not predict time to engraftment.     

Peripheral blood progenitor cell (PBPC) counts during steady-state hematopoiesis allow to estimate the yield of mobilized PBPC after filgrastim (R-metHuG-CSF)-supported cytotoxic chemotherapy [see comments]

Peripheral blood progenitor cells (PBPC) can be mobilized using cytotoxic chemotherapy and cytokines. There is a substantial variability in the yield of hematopoietic progenitor cells between patients. We were looking for predictive parameters indicating a patient's response to a given mobilization regimen. Multiparameter flow- cytometry analysis and clonogenic assays were used to examine the hematopoietic progenitor cells in bone marrow (BM) and peripheral blood (PB) before filgrastim (R-metHuG-CSF; Amgen, Thousand Oaks, CA)- supported chemotherapy and in PB and leukapheresis products (LPs) in the recovery phase. Fifteen patients (four with high-grade non- Hodgkin's lymphoma [NHL], two with low-grade NHL, two with Hodgkin's disease, two with multiple myeloma, three with breast cancer, one with ovarian cancer, and one with germ cell tumor) were included in this study. The comparison of immunofluorescence plots showed a homogenous population of strongly CD34+ cells in steady-state and mobilized PB whereas in steady-state BM, the CD34+ cells ranged from strongly positive with continuous transition to the CD34- population. Consistent with the similarity in CD34 antigen expression, a correlation analysis showed steady-state PB CD34+ cells (r = .81, P < .001) and colony- forming cells (CFCs; r = .69, P < .01) to be a measure of a patient's mobilizable CD34+ cell pool. Individual estimates of progenitor cell yields could be calculated. With a probability of 95%, eg, 0.4 steady- state PB CD34+ cells x 10(6)/L allowed to collect in six LPs 2.5 x 10(6) CD34+ cells/kg, the reported threshold-dose of progenitor cells required for rapid and sustained engraftment after high-dose therapy. For the total steady-state BM CD34+ cell population, a weak correlation (r = .57, P < .05) with the mobilized CD34+ cells only became apparent when an outlier was removed from the analysis. Neither the CD34+ immunologic subgroups defined by the coexpression of the myeloid lineage-associated antigens CD33 or CD45-RA or the phenotypically primitive CD34+/HLA-DR- subset nor the BM CFC count had a predictive value for the mobilization outcome. This may be caused by the additional presence of maturing progenitor cells in BM, which express lower levels of the CD34 antigen and do not circulate. Our results permit us to recognize patients who are at risk to collect low numbers of progenitor cells and those who are likely to achieve sufficient or high progenitor cell yields even before mobilization chemotherapy is administered.