Mobilisation of peripheral blood stem cells with IVE and G-CSF improves CD34+ cell yields and engraftment in patients with non-Hodgkin's lymphomas and Hodgkin's disease

Anticipation of Relapse and Acute Graft-Versus-Host Disease after Allogeneic Peripheral Blood Stem Cell Transplantation: The Fundamental Role of Antigen-Presenting (Dendritic) Cells

Background

Dendritic cells (DCs) are antigen-presenting cells. In humans two distinct lineages of DCs exist: DC1 and DC2. Efforts to explore the role of DCs in acute graft-versus-host disease (aGVHD) after allogeneic peripheral blood stem-cell transplantation (PBSCT) are gaining traction. However, further research is needed to identify particular lineages and their values in terms of developing an evidence-based aGVHD- or relapse-prevention strategy. We monitored DC counts and subsets in PBSC grafts while harvesting stem cells in recipients to elucidate their value in anticipating disease relapse or aGVHD.

Methods

We enrolled 29 participants. Using fluorescence-activated cell sorting, total counts/kg of CD34⁺, DCs, and DC subsets were analyzed in 29 PBSC-graft components using CMRF44, CD11c, and CD4 monoclonal antibodies (MoAbs).

Results

In the 29 grafts, we detected a significant positive correlation (P<0.01) between DCs and both DC1 and DC2. Significantly higher counts (P<0.01) of DCs and DC1 in those who had developed aGVHD (nine cases) were also observed. Relapsed cases (two) were also associated with higher counts of DCs and DC2. A significant positive correlation (P<0.05), was recorded between DCs and DC1 counts and the day of myeloid engraftment, while this was not detected on the day of platelet engraftment. Myeloid engraftment transpired earlier in patients without aGVHD. Increased DC-graft numbers, particularly DC1 measured by CD11c Moabs, were associated with aGVHD. Recipients of higher numbers of CD4^bright DCs had an increased risk of relapse after allogeneic PBSCT.

Conclusion

This study analyzed DCs in PBSC grafts, using novel specific MoAbs and flow cytometry. Our data showed that higher donor DC1 counts were linked to the incidence of aGVHD and DC2 with relapse. We propose a fundamental role for DC-graft monitoring in anticipating aGVHD and disease relapse.

Dose-Modified Ifosfamide, Epirubicin, and Etoposide is a Safe and Effective Salvage Therapy with High Peripheral Blood Stem Cell Mobilization Capacity for Poorly Mobilized Hodgkin's Lymphoma and Non-Hodgkin's Lymphoma Patients

A dose modified ifosfamide, epirubicin, and etoposide (IVE) regimen was prospectively assessed for its efficacy in mobilizing peripheral blood stem cells for autologous transplantation. Two patients with Hodgkin's lymphoma and two with non-Hodgkin's lymphoma who were undergoing stem cell therapy were studied. All patients had a history of multiple treatments with insufficient stem cell mobilization. The dose modified IVE regimen consisted of ifosfamide 3 g/m(2) intravenously (IV) administered on days 1-2 in combination with epirubicin 50 mg/m(2) IV on day 1 and etoposide 200 mg/m(2) (100 mg/m(2) in two patients with complete remission) IV on days 1-3. The ifosfamide dosage was reduced to two-thirds of the original protocol. A substantial high yield of CD34(+) cells was achieved when patients were treated with a dose-modified IVE regimen, compared with that during the previous regimen (two with the ifosfamide, carboplatin, and etoposide [ICE] regimen, one with high-dose cyclophosphamide and one with the original IVE regimen). Two patients who had refractory and residual disease received a 200 mg/m(2) dose of etoposide, which resulted in tumor reduction (one patient with complete remission and one with further reduction in tumor size). After the IVE regimen, all four patients had a sufficient yield of CD34(+) cells in total, which was available for stem cell transplantation. Hematological and non-hematological toxicities were comparable in all regimens. This single-center prospective study demonstrated that the dose-modified IVE regimen can be used as a safe treatment with high mobilizing efficacy in heavily pretreated lymphoma patients.

The effect of gradual increment in rhG-CSF dose on stem cell yields in patients with multiple myeloma mobilized with intermediate dose cyclophosphamide plus rhG-CSF

Cyclophosphamide along with recombinant human granulocyte-colony stimulating factor (rhG-CSF) is a commonly used strategy for mobilization. However, the optimal timing for rhG-CSF initiation after cyclophosphamide has not been determined as conclusively as has the G-CSF dose. In this paper, we aimed to present gradual dose increment of rhG-CSF between the third day of mobilization and time to apheresis that is started with 5 μg/kg (from day 3 to day 7) and continued with 10 μg/kg (from day 8 to time to apheresis) for peripheral blood stem cell (PBSC) mobilization in multiple myeloma (MM) patients and its effect on stem cell yield and mobilization success. Data from 30 consecutive patients with MM who underwent PBSC mobilization between October 2011 and June 2013, were retrospectively reviewed. While twenty-eight of 30 patients (93.3%) were successfully mobilized, 2 patients (6.7%) had mobilization failure. The final median CD34+ cell dose harvested from the patients was 9.5×10(6)/kg. The median number of apheresis was 2.5 (range, 0-3). Twenty-four patients (80%) yielded >2×10(6) CD34+ cells/kg in one apheresis procedure. In conclusion, our regimen might be used to decrease the mobilization failure regarding the low dose rhG-CSF use and provide a cost effective strategy.

Which regimen is better for stem cell mobilization of lymphoma patients?

Although chemotherapy combined with G-CSF is an effective method for hematopoietic stem cell mobilization, standard chemotherapy protocol leading to best stem cell yield is not defined. In our study, we aimed to assess the impact of chemotherapy choice on mobilization outcome in lymphoma patients. Patients were mobilized with cyclophosphamide (n:15), ASHAP (n:11) or VGEPP (n:12) protocols. Groups were similar according to collected CD34+ cell count, total nucleated cell count and median apheresis days. Five out of fifteen (33%) patients could not be mobilized in Cy group but there was only one failed mobilization attempt in both salvage groups (9% with ASHAP vs 8% with VGEPP). In conclusion, we showed that VGEPP and ASHAP are safe protocols in terms of stem cell mobilization and have similar mobilization capacity as cyclophosphamide alone.

Mobilization strategies for the collection of peripheral blood progenitor cells: Results from a pilot study of delayed addition G-CSF following chemotherapy and review of the literature

OBJECTIVE

Given the potential to limit cost, we conducted a pilot study evaluating delayed, low-dose granulocyte colony-stimulating factor (G-CSF) following chemotherapy for the procurement of peripheral blood progenitor cells (PBPCs) for autologous transplantation and reviewed the relevant literature.

PATIENTS AND METHODS

Twenty-eight patients with various malignancies received cyclophosphamide 4 gm/m(2) and paclitaxel 170 mg/m2 followed by G-CSF 300 microg/d or 480 microg/d starting day +5 until two to four daily large volume leukapheresis yielded > or =5.0 x 10(6) CD34+ cells. We searched MEDLINE, Pubmed, and EMBASE databases from 1990 to the present to identify papers on PBPC procurement using delayed G-CSF (starting day +4 or later) following chemotherapy.

RESULTS

G-CSF was administered for a median of 9 days at an average cost of 1260 USD per 70-kg patient. Collection was initiated at a median of 12 days after chemotherapy. A median 2.5 (range 2-4) apheresis were performed yielding an average daily CD34+ collection of 6.9 x 10(6)/kg (range 0.35-56.7). After one apheresis, 82% and 57% of patients collected > or =2.5 x 10(6)/kg and > or =5.0 x 10(6)/kg, respectively. Ultimately, 89% collected > or =5.0 x 10(6)/kg. Febrile neutropenia and catheter-related infection developed in five and two patients, respectively. All patients proceeded to transplantation and engrafted successfully with a median of 14.9 x 10(6)/kg (range 1.05-113) cells infused. Eleven published reports were identified involving 590 patients of whom 498 received G-CSF at a dose range of 250 microg/d to 10 microg/kg/d starting day +4 to 15 for a period of 4 to 9 days for PBPC procurement. Among these reports, 62 to 100% and 33 to 96% of patients collected > or =2 to 2.5 x 10(6) and > or =5.0 x 10(6) CD34+ cells, respectively.

CONCLUSION

The use of delayed, low-dose G-CSF plus chemotherapy for stem cell mobilization was feasible and provides further evidence supporting this potentially cost-effective strategy. A review of the literature supports our findings and emphasizes the need for larger studies to address this issue.

IGEV regimen and a fixed dose of lenograstim: an effective mobilization regimen in pretreated Hodgkin's lymphoma patients

We explored the efficacy of the IGEV regimen (ifosfamide, gemcitabine, vinorelbine and prednisone) combined with a fixed dose of lenograstim (263 mug/day) to mobilize peripheral blood stem cells (PBSCs) in 90 Hodgkin's lymphoma patients. The median total CD34+ cells/mul peak, colony-forming units granulocyte-macrophage and white blood cells for all individual collection sets were 85/mul, 12 x 10(4)/kg and 20 700/mul, respectively. An adequate number of CD34+ cells (more than 3 x 10(6) or 6 x 10(6) CD34+ cells/kg depending on whether single or tandem high-dose chemotherapy was used) were collected in 89 out of 90 (98.7%) mobilized patients, whereas the only failure reached 2.3 x 10(6) CD34+ cells/kg. The median CD34+ cell collections were 11 x 10(6)/kg (range 2.3-39 x 10(6)/kg) and 10 x 10(6)/kg (range 6-22.0 x 10(6)/kg) with a median of 1 and 2 leukaphereses for patients eligible for single high-dose treatment and for candidates for tandem transplant, respectively. Target yields were reached in 71.43 and 49.09% and additionally in 17.14 and 43.64% of cases after the first and second apheresis procedures, respectively. Hematological and non-hematological side effects were acceptable, and no toxic deaths occurred. Thirty-four patients received a single and 47 received tandem transplantation with rapid engraftment. These results confirm that the IGEV regimen with lenograstim support can be used successfully and safely to mobilize PBSCs.

Outpatient fractionated ifosfamide, carboplatin and etoposide as salvage therapy in relapsed and refractory non-Hodgkin's and Hodgkin's lymphoma

We have treated 75 transplant-eligible patients with relapsed or refractory lymphoma using an outpatient-based fractionated regimen of ifosfamide, carboplatin and etoposide (ICE) for both salvage and stem cell mobilisation. Patients included DLBC (n = 33), follicular (n = 23), NK/T-cell (n = 3), mantle cell (n = 3) and Hodgkin's lymphoma (n = 13). Cycles of outpatient ICE were given every 21 days and consisted of: ifosfamide 5000 mg/m(2) i.v. fractionated into three equally divided doses and infused over 2-3 h on days 1-3, carboplatin (mg dose = 5 x AUC) i.v. over 1 h on day 1; and etoposide 100 mg/m(2) i.v. daily on days 1-3, plus filgrastim 5 microg/kg/day. Most patients with indolent lymphoma also received rituximab. The median age of patients was 52 years (range 26-69 years). Patients received a mean of 2.8 cycles of ICE. Non-haematological toxicities included grade 1/2 CNS toxicity in four patients, cardiac toxicity in two, reversible renal impairment and haematuria in one each. Haematological toxicity included grades III/IV thrombocytopenia and neutropenia with at least one cycle of ICE in 71% and 72% of patients, respectively. The median time to PBSC harvest was 14 days (range 10-20 days), while the median CD34(+) cell yield was 4.8 x 10(6)/kg (range 2.3-37.8). Five patients (7%) failed to mobilise PBSCs. The overall response rate to ICE was 89%, comprising 29% who achieved a CR and 60% who achieved a PR; for DLBCL, the overall response rate was 85% including 36% who achieved a CR and 49% who exhibited a PR. At a median follow-up of 24 months, the Kaplan-Meier estimates of the overall and event-free survival for all patients were 65% and 42%, respectively. For patients with DLBCL overall and event-free survival figures were 51% and 35%, respectively, at a median follow-up of 14 months. These data confirm the efficacy and tolerability of outpatient fractionated ICE as both a salvage and mobilisation regimen in relapsed/refractory lymphoma.

Mobilization of peripheral blood stem cells in CLL patients after front-line fludarabine treatment

Autologous peripheral blood stem cell transplantation is performed in an increasing number of chronic lymphocytic leukaemia (CLL) patients who are in the first remission following fludarabine treatment. There are contradictory data about the adverse impact of fludarabine on stem cell harvest. We analysed retrospectively mobilization results in 56 poor-risk CLL patients (median age: 56 years) who underwent first-line treatment with fludarabine and cyclophosphamide. The mobilization, consisting of cyclophosphamide 3 g/m(2) and granulocyte colony-stimulating factor (G-CSF) 10 microg/kg per day, was performed with a median of 77 days following the last fludarabine course. The target yield was >or=2.0x10(6) CD34+ cells/kg. The procedure was successful in 23 (41%) patients. A median of 3.3x10(6) CD34+ cells/kg was collected per patient. The successful mobilization was associated with a longer interval from the last chemotherapy (>2 months). The mobilization result was not influenced by the number of fludarabine cycles. No correlation was found in other parameters such as disease stage at diagnosis, disease status at stimulation or age. The poorly mobilized patients had significantly lower prestimulation blood counts (platelets, WBC and haemoglobin). Our data show that fludarabine does not generally prevent the stem cell mobilization; nevertheless, mechanisms related to the impact of fludarabine on stem cell harvest must be further investigated.

Outpatient-based ifosfamide, carboplatin and etoposide (ICE) chemotherapy in transplant-eligible patients with non-Hodgkin's lymphoma and Hodgkin's disease

We have treated 38 transplant-eligible patients with relapsed/refractory non-Hodgkin's lymphoma and Hodgkin's disease using an outpatient-based regimen of ifosfamide, carboplatin and etoposide (ICE) for both salvage and peripheral blood stem cell mobilisation. Patients included relapsed or refractory diffuse large B-cell lymphoma (n = 17), follicular lymphoma (n = II), T-cell lymphoma (n = 2), mantle cell lymphoma (n = 2) and Hodgkin's disease (n = 6). Seven patients with diffuse large B-cell lymphoma and three patients with follicular lymphoma (26%) were considered chemorefractory. Cycles of ICE therapy were administered every 21 days as an outpatient and consisted of ifosfamide 5000 mg/m2 intravenously (i.v.) fractionated into three equally divided doses over 3 days, carboplatin [mg dose = 5 x area under the curve (AUC)] i.v. on day 1 and etoposide 100 mg/m2- i.v. daily for 3 days. Subsequently. granulocyte colony-stimulating factor (G-CSF)5 microg/kg subcutaneously (s.c.) was administered daily from day +5. Of the I I follicular lymphoma patients, 10 also received rituximab with ICE therapy. Median age of patients was 52 years (range 30-65). Patients received a mean of 2.6 cycles (range 1-4) of ICE. There were no toxic deaths and no significant non-haematological toxicities secondary to ICE therapy. Grade IV thrombocytopenia and grade IV neutropenia with at least one cycle of ICE were seen in 47% and 53% of patients, respectively. Median time to peripheral blood stem cell (PBSC) harvest was 14 days (range 10-20). while the median CD34+ cell yield was 5.2 x 10(6) cells/kg(range 2.3 x 10(6)-27.2 x 10(6)). Only one of the ICE-responders failed to mobilise PBSCs. The overall response rate to ICE was 87%. comprising 14 patients (37%) who achieved a complete response (CR) and 19 (50%) who achieved a partial response (PR). A total of 30 patients have undergone autologous stem cell transplantation(SCT) while two follicular lymphoma patients have received a non-myeloablative allogeneic SCT. Follow-up is short: however, the Kaplan-Meier estimate of the proportion of patients alive and event-free at a median follow-up of 11 months is 80% and 59%, respectively. Event-free survival for patients who achieved a CR after ICE and transplantation is 88% versus 45% for those who achieved a PR. These data confirm the efficacy and tolerability of fractionated ICE chemotherapy as both a salvage and mobilisation regimen that can be readily delivered in an outpatient setting.

Impact of chemotherapy regimen and hematopoietic growth factor on mobilization and collection of peripheral blood stem cells in cancer patients

Various chemotherapy regimens, combined with recombinant human granulocyte colony-stimulating factor(rhG-CSF) or recombinant granulocyte-macrophage CSF (rhGM-CSF) are used in cancer patients to mobilize and collect peripheral blood stem cells (PBSC). In this retrospective study, we evaluated and compared the efficacy of such regimens in 262 patients with different types of malignant diseases. The following chemotherapy regimens were applied: ifosfamide-etoposide-cisplatin or bleomycin (n = 96; mainly patients with testicular cancer); ifosfamide-etoposide plus or minus cytosine arabinoside (Ara-C) or vincristine (VCR)(n = 52; mainly patients with lymphoma); cyclophosphamide-anthracycline (n = 53; mainly patients with breast cancer); intermediate to high dose (ID-HD) cyclophosphamide (n = 37; mainly patients with breast or ovarian cancer. or multiple myeloma; and others (n = 24). rhG-CSF or rhGM-CSF, each at an average daily dose of 5 microg/kg body weight, were used in 166 and 96 patients, respectively. The study evaluated and compared the efficacy of these two cytokines. In patients receiving rhG-CSF, CD34+ cells could be collected earlier (median: day 14 versus day 16) and there was a significantly higher white blood cell count (WBC)(median 11,350 versus 5550/microl) and CD34+ cell count (median 88 versus 43/microl) at the start of apheresis, and a significantly higher CD34+ cell yield (median 7.4 x 10(6) versus 4.6 x 10(6)/kg) than in patients who receivedrhGM-CSF. Among the various chemotherapeutic regimens used, each combined with rhG-CSF, ifosfamide-etoposide plus or minus Ara-C or VCR mobilized a significantly higher number of CD34+ cells (median 119/microl) and produced a significantly higher harvest of these cells (median 13 x 10(6)/kg) than cyclophosphamide-anthracycline (median 87/microl and 7 x 10(6)/kg, respectively) or ID-HD cyclophosphamide (median 59/microl and 5 x I 0(6)/kg, respectively). Ifosfamide-etoposide plus or minus Ara-C or VCR was also superior to ifosfamide-etoposide-cisplatin or bleomycin (median 78/microl and 9 x 10(6)/kg, respectively), but at borderline significance. The outcome of PBSC mobilization and collection appeared to be negatively influenced by the number of relapses before the current salvage treatment. These data indicate that mobilization and collection of PBSCstrongly depend on the type of hematopoietic growth factor and chemotherapeutic regimen used. The data further show rhG-CSF is a more effective growth factor than rhGM-CSF and ifosfamide-etoposide-based regimens, particularly ifosfamide-etoposide plus or minus Ara-C or VCR, are highly effective regimens in mobilizing and collecting CD34+ cells.

Is chemotherapy scoring useful to predict progenitor cell mobilisation in patients with non-Hodgkin's lymphoma?

About 10-30% of patients with non-Hodgkin's lymphoma (NHL) intended to receive high-dose therapy are difficult to mobilise. Damage to the stem cell pool caused by previous chemotherapy may be an important factor in predicting progenitor cell mobilisation. We have analysed associations between chemotherapy score and efficiency of progenitor cell mobilisation in 120 consecutive NHL patients mobilised with intermediate-dose cyclophosphamide (4 g/m(2)) plus G-CSF. The original chemotherapy scoring system proposed by Drake et al was applicable in only 27% of our patients and was not predictive for mobilisation outcome. Therefore we made an improved scoring system for previous chemotherapy by adding new drugs. Altogether, 111 patients (93%) could be scored. Our chemotherapy score showed an inverse correlation with the peak blood CD34(+) count measured after the mobilisation (r=-0.214, P=0.024) and with the number of CD34(+) cells collected (r=-0.234, P=0.02). However, in the receiver operating characteristics curve, no threshold value could be detected for chemotherapy score predicting mobilisation failure. Thus, both the original scoring system as well as our more widely applicable scoring system seem to be of limited value in predicting progenitor cell mobilisation in patients with NHL.

Harvesting of autologous blood stem cells after a mobilising regimen with low-dose cyclophosphamide

Although high-dose cyclophosphamide (HD-CTX) is commonly used as a mobilising regimen for autologous peripheral blood stem cell (PBSC) collection, significant morbidity and insufficient harvesting may complicate the procedure. Alternative regimens and lower doses of cyclophosphamide (CTX) have been investigated as possible ways of overcoming these difficulties. Low-dose CTX (1.5 g/m2) was administered to 102 lymphoma patients as an autologous PBSC mobilising regimen. The collection of 6 x 10(6) CD34+ cells/kg was chosen as the target of the apheresis sessions, whereas 3 x 10(6)/kg were considered the minimum necessary to perform autologous stem cell transplantation (ASCT) safely. The apheretic sessions were started a median of eight days after CTX administration; a median of two aphereses was required. More than 6 x 10(6) CD34+ cells/kg were collected from 78 patients, between 3 and 6 x 10(6)/kg from 19, and fewer than 3 x 10(6)/kg from 5, two of whom underwent bone marrow harvesting and one a successful second PBSC harvesting session using the same mobilising regimen. Eighty-two patients underwent autografting, six of whom received a second transplant after relapse (five using autologous PBSCs coming from the first apheretic course). Low-dose CTX proved to be a safe and effective regimen for autologous PBSC mobilization and also compared favourably with alternative regimens in terms of the rate of harvesting insufficiency. This does not imply that low-dose CTX is the best mobilising regimen for all patients, and the identification of prognostic factors predicting mobilising potential may help in choosing the best individualised regimen.

A European reference protocol for quality assessment and clinical validation of autologous haematopoietic blood progenitor and stem cell grafts

Recently, the regulatory authorities have begun to show interest in haematopoietic stem cell products. On a professional rather than a regulatory basis, the International Society for Hematotherapy and Graft Engineering (ISHAGE) has established the Foundation for the Accreditation of Haematopoietic Cell Therapy (FACHT), which has drawn up guidelines for standards and accreditation of such activity. In Europe, the regulatory environment with regard to haematopoietic stem cell grafts, processing and storage are currently less stringent. However, in 1998 the European Joint Accreditation Committee Euro-ISHAGE/EBMT (JACIE) prepared a regulatory document 'Standards for Blood and Marrow Progenitor Cell Collection, Processing and Transplantation' which was approved by the EBMT General Assembly. The major objectives were to promote quality of medical and laboratory practice in haematopoietic progenitor cell transplantation. The standards extend and detail the pre-existing activity of EBMT centres including all phases of collection, processing and administration of these cells. This is the platform for the proposed reference protocol for CD34(+) cell enumeration and clinical validation of quality assessment to ensure that appropriate standards of work and product quality are established and will be maintained.

Phase II study of a high-dose ifosfamide-based chemotherapy regimen with growth factor rescue in recurrent aggressive NHL. High response rates and limited toxicity, but limited impact on long-term survival

The purpose of the study was to evaluate in patients with recurrent intermediate-grade NHL, the tolerance to and efficacy of an intensive salvage regimen consisting of high doses of ifosfamide, etoposide and mitoxantrone with G-CSF support, followed by autologous stem cell transplantation and to identify prognostic factors for survival in patients with recurrent aggressive lymphoma. Patients with recurrent intermediate-grade NHL under the age of 60 years were eligible. Induction consisted of ifosfamide 10 g/m(2) and etoposide 900 mg/m(2) with G-CSF 5 microg/kg twice a day. Upon recovery, patients underwent stem cell apheresis. Patients achieving complete remission (CR) underwent autologous stem cell transplantation using BEAM conditioning. Those with partial remission (PR) received treatment with ifosfamide 10 g/m(2), mitoxantrone 20 mg/m(2) and G-CSF 5 microg/kg. Those with CR received BEAM, those with PR received cyclophosphamide 4.5 g/m(2), etoposide 1200 mg/m(2) and cisplatin 135 mg/m(2) with stem cell rescue followed by BEAM. Antibiotic prophylaxis was given with all treatment cycles. The results were compared with those obtained in a prior study that used MINE-ESHAP salvage. Forty-four patients with recurrent intermediate-grade NHL were enrolled between March 1994 and September 1996. Median age was 50 years (24-61). Eleven patients had transformed lymphoma and seven had a T cell phenotype. Response rate to the high-dose ifosfamide regimen was 77% +/- 12% after two cycles and the complete response rate was 41% +/- 14%. Myelosuppression was profound but short. Median nadir ANC was 0 and the median duration of ANC <0.5 x 10(9)/l was 6 days (range 3-12). No severe infections occurred; 55% of the patients required blood transfusion and 42% required platelet transfusions. Myelosuppression and transfusion requirements were similar after the first and second cycles. Thirty-five of the 44 patients proceeded to autologous stem cell transplantation and one transplant-related death occurred. With a median follow-up of 52 months, progression-free survival at 2 years is 38% +/- 14% and survival is 52% +/- 15%. Data from these 44 patients were pooled with data on 53 patients who had received salvage treatment with MINE-ESHAP, for a multivariate analysis of prognostic factors. In multivariate analysis, serum LDH was strongly associated with survival. The use of a more intensive salvage regimen, did not result in a significant increase in long-term outcome, despite a high response rate. In conclusion, duration of treatment, response rates, treatment-related mortality and survival compare favorably with previous salvage regimens, but recurrence remains a major problem. Long-term survival in recurrent large cell lymphoma is influenced more by disease characteristics than by the type of salvage regimen used.

Mobilization of hematopoietic stem cells

Hematopoietic stem cell transplantation has been extensively exploited as a therapeutic and research modality and has revolutionized current patient care. At present, more and more medical centers use peripheral blood progenitor cells for transplantation by mobilizing hematopoietic stem cells from bone marrow to peripheral blood because of potential advantages of peripheral blood stem cell transplantation over bone-marrow transplantation. Different effective mobilization regimens have been developed recently with chemotherapeutic agents, hematopoietic growth factors or their combination. This article reviews current developments related to hematopoietic stem cell mobilization including the biology of hematopoietic stem cells, strategies for mobilization, management for mobilization failure, mechanisms of mobilization, and side effects during mobilization. Finally, the Initiation-Amplification-Emigration-Adaptation Model is proposed to help aid understanding of the mechanisms of hematopoietic stem cell mobilization and to stimulate development of novel and optimal mobilization strategies for patient care.