Peripheral Blood Stem Cell Transplantation Group Research Articles

Hematopoiesis in the spleen after engraftment in unrelated cord blood transplantation evaluated by 18F-FLT PET imaging.

Cord blood is an important donor source for allogeneic hematopoietic stem cell transplantation (allo-HSCT), with its unique composition and quality of hematopoietic cells. The proliferation site and potency of infused hematopoietic stem cells in humans may vary between stem cell sources. We investigated this possibility in a prospective, exploratory study to assess hematopoietic dynamics using the radiopharmaceutical 3'-deoxy-3'-18F-fluorothymidine (18F-FLT), a thymidine analog used in positron emission tomography imaging, before allo-HSCT and on days 50 and 180 after allo-HSCT. We evaluated 11 patients with hematological malignancies who underwent allo-HSCT [five with peripheral blood stem cell transplantation (PBSCT) and six with unrelated cord blood transplantation (UCBT)]. Before allo-HSCT, 18F-FLT uptake did not differ between the two groups. At day 50, 18F-FLT uptake in the spleen was significantly greater in the UCBT group than in the PBSCT group (p = 0.0043), with no difference in whole-body bone marrow. At day 180, the differences in spleen uptake had diminished, and there were no differences between groups in whole-body bone marrow or the spleen, except for the sternum. The persistence of splenic hematopoiesis after engraftment in the UCBT group may reflect the complex systemic homing and proliferation mechanisms of cord blood hematopoietic cells.

Dynamic comparison of early immune reactions and immune cell reconstitution after umbilical cord blood transplantation and peripheral blood stem cell transplantation.

Umbilical cord blood transplantation (UCBT) and peripheral blood stem cell transplantation (PBSCT) are effective allogeneic treatments for patients with malignant and non-malignant refractory hematological diseases. However, the differences in the immune cell reconstitution and the immune reactions during initial stages post-transplantation are not well established between UCBT and PBSCT. Therefore, in this study, we analyzed the differences in the immune reactions during the early stages (days 7-100 post-transplantation) such as pre-engraftment syndrome (PES), engraftment syndrome (ES), and acute graft-versus-host disease (aGVHD) and the immune cell reconstitution between the UCBT and the PBSCT group of patients. We enrolled a cohort of patients that underwent UCBT or PBSCT and healthy controls (n=25 each) and evaluated their peripheral blood mononuclear cell (PBMC) samples and plasma cytokine (IL-10 and GM-CSF) levels using flow cytometry and ELISA, respectively. Our results showed that the incidences of early immune reactions such as PES, ES, and aGVHD were significantly higher in the UCBT group compared to the PBSCT group. Furthermore, in comparison with the PBSCT group, the UCBT group showed higher proportion and numbers of naïve CD4+ T cells, lower proportion and numbers of Tregs, higher proportion of CD8+ T cells with increased activity, and higher proportion of mature CD56dim CD16+ NK cells during the early stages post-transplantation. Moreover, the plasma levels of GM-CSF were significantly higher in the UCBT group compared to the PBSCT group in the third week after transplantation. Overall, our findings demonstrated significant differences in the post-transplantation immune cell reconstitution between the UCBT and the PBSCT group of patients. These characteristics were associated with significant differences between the UCBT and the PBSCT groups regarding the incidences of immune reactions during the early stages post transplantation.

Correlation between immune reconstitution and chronic graft-versus-host disease after unrelated cord blood transplantation and sibling peripheral blood stem cell transplantation

目的探究恶性血液病患者非血缘脐血干细胞移植（UCBT）和同胞外周血干细胞移植（PBSCT）后免疫重建与慢性移植物抗宿主病（cGVHD）的关系。方法以2018年3月至2019年8月在中国科学技术大学附属第一医院行UCBT（96例）和PBSCT（28例）的患者为研究对象。采用流式细胞术检测两组患者移植后第1、3、6、9、12个月外周血免疫细胞，并根据是否发生cGVHD进行分组，探究两种移植类型的免疫细胞重建与cGVHD之间的相关性。结果①UCBT组移植后1年中重度cGVHD累积发生率显著低于PBSCT组［9.38％（95％CI 3.35％～15.02％）对28.57％（95％CI 9.72％～43.50％），P＝0.008］；UCBT组移植后2年cGVHD、中重度cGVHD累积发生率均低于PBSCT组［15.60％（95％CI 9.20％～23.60％）对32.10％（95％CI 15.80％～49.70％），P＝0.047；10.40％（95％CI 5.30％～17.50％）对28.60％（95％CI 13.30％～46.00％），P＝0.014］。②UCBT组CD4+T细胞计数在移植后第6、9、12个月均高于PBSCT组［59.00（36.70～89.65）×107/L对31.40（18.10～44.00）×107/L，P<0.001；71.30（49.60～101.45）×107/L对41.60（25.82～56.27）×107/L，P<0.001；83.00（50.17～121.55）×107/L对44.85（31.62～62.10）×107/L，P<0.001］，CD4 +T细胞比例始终高于PBSCT组（P<0.05）。PBSCT组B细胞计数和比例在移植后第1个月高于UCBT组［0.70（0.30～1.70）×107/L对0.10（0～0.30）×107/L，P<0.001；0.45％（0.30％～2.20％）对0.20％（0.10％～0.40％），P＝0.002］；UCBT组B细胞计数和比例在移植后第9、12个月高于PBSCT组［53.80（28.00～103.20）×107/L对23.35（5.07～35.00）×107/L，P<0.001；21.45％（11.80％～30.45％）对9.00％（3.08％～16.73％），P<0.001。66.70（36.97～98.72）×107/L对20.85（7.72～39.40）×107/L，P<0.001；22.20％（14.93％～29.68）％对8.75％（5.80％～18.93％），P<0.001］。UCBT组调节性B细胞（Breg）计数和比例在移植后第6、9和12个月高于PBSCT组［1.23（0.38～3.52）×107/L对0.05（0～0.84）×107/L，P<0.001；5.35％（1.90％～12.20％）对1.45％（0％～7.78％），P＝0.002。2.25（1.07～6.71）×107/L对0.12（0～0.77）×107/L，P<0.001；6.25％（2.00％～12.33％）对0.80％（0％～5.25％），P<0.001。3.69（0.83～8.66）×107/L对0.46（0～0.93）×107/L，P<0.001；6.15％（1.63％～11.75％）对1.40％（0.18％～5.85％），P<0.001］。③UCBT患者中非cGVHD组的B细胞计数在移植后第6、12个月均高于中重度cGVHD组（P＝0.038，P＝0.043）；非cGVHD组的B细胞比例在移植后第6个月高于中重度cGVHD组（P＝0.049）。UCBT患者中非cGVHD组的Breg细胞计数在移植后第6、9、12个月高于中重度cGVHD组（P＝0.006，P＝0.028，P＝0.050）；非cGVHD组的Breg细胞比例在移植后第9个月高于中重度cGVHD组（P＝0.038）。④PBSCT患者中非cGVHD组的B和Breg细胞绝对数和比例与中重度cGVHD组差异无统计学意义。结论在免疫细胞重建过程中，UCBT组的Breg细胞高于PBSCT组，并且两种移植类型的非cGVHD组的Breg细胞始终较中重度cGVHD组高，表明Breg细胞能够降低cGVHD的发生，揭示了UCBT组cGVHD发生率较低的可能原因。

A novel stem cell therapy for hepatitis B virus-related acute-on-chronic liver failure.

The aim of this study was to propose a stem cell therapy for hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF) based on plasma exchange (PE) for peripheral blood stem cell (PBSC) collection and examine its safety and efficacy. Sixty patients (n=20 in each group) were randomized to PE (PE alone), granulocyte colony-stimulating factor (G-CSF) (PE after G-CSF treatment), and PBSC transplantation (PBSCT) (G-CSF, PE, PBSC collection and hepatic artery injection) groups. Patients were followed-up for 24 weeks. Liver function and adverse events were recorded. Survival analysis was performed. PBSCT improved blood ammonia levels at 1 week (P<0.05). The level of total bilirubin, international normalized ratio, and creatinine showed significant differences in the 4th week of treatment (P<0.05). The survival rates of the PE, G-CSF, and PBSCT groups were 50, 65, and 85% at 90 days (P=0.034). There was a significant difference in 90-day survival between the PE and PBSCT groups (P=0.021). The preliminary results suggested that PBSCT was safe, with a possibility of improved 90-day survival in patients with HBV-ACLF.

Comparison of unrelated cord blood transplantation and HLA-identical sibling peripheral blood stem cell transplantation for the treatment of adult hematological malignancies

目的比较单份清髓非血缘脐血移植（UCBT）与HLA相合同胞外周血干细胞移植（PBSCT）治疗成人恶性血液病的疗效。方法自2011年4月1日至2015年12月31日，共81例单份清髓UCBT与57例HLA相合同胞PBSCT患者入组进行比较。所有患者均采用清髓性预处理方案，环孢素A联合霉酚酸酯预防移植物抗宿主病（GVHD）。结果移植后42 d（+42 d）UCBT组中性粒细胞累积植入率为95.0%（95%CI 87.0%~98.1%），同胞PBSCT组为100%（P=0.863）。+100 d UCBT组血小板累积植入率低于同胞PBSCT组[87.3%（95%CI 76.8%~93.1%）对98.2%（95%CI 87.3%~99.7%），P=0.005]。+100 d UCBT组Ⅱ~Ⅳ度急性GVHD、Ⅲ/Ⅳ度急性GVHD的累积发生率分别为18.2%（95%CI 9.1%~26.4%）、10.4%（95%CI 3.3%~16.9%），同胞PBSCT组分别为8.9%（95%CI 1.1%~16.1%）、7.1%（95%CI 1.4%~13.7%），差异均无统计学意义（P=0.142，P=0.521）。UCBT组3年慢性GVHD、广泛型慢性GVHD累积发生率均低于同胞PBSCT组[14.9%（95%CI 5.2%~23.5%）对35.2%（95%CI 19.4%~47.8%），P=0.008；11.2%（95%CI 2.9%~18.7%）对31.4%（95%CI 16.2%~43.9%），P=0.009]。UCBT组、同胞PBSCT组3年移植相关死亡率（TRM）差异无统计学意义[30.1%（95%CI 19.2%~41.7%）对23.2%（95%CI 13.1%~35.0%），P=0.464]。UCBT组3年疾病复发率低于同胞PBSCT组[12.9%（95%CI 6.6%~21.5%）对24.3%（95%CI 13.5%~36.8%），P=0.039]。UCBT、同胞PBSCT组3年总生存率、无病生存率差异均无统计学意义[58.6%（95%CI 45.4%~69.7%）对54.8%（95%CI 39.9%~67.4%），P=0.634；57.0%（95%CI 44.0%~68.0%）对52.4%（95%CI 38.2%~64.9%），P=0.563]。UCBT组3年无GVHD及复发生存（GRFS）率高于同胞PBSCT组[55.7%（95%CI 44.1%~65.8%）对42.9%（95%CI 29.8%~55.3%），P=0.047]。结论对于成人恶性血液病，UCBT与HLA相合同胞PBSCT具有相似的急性GVHD发生率、TRM、总生存率和无病生存率，但UCBT组具有较低的慢性GVHD发生率及疾病复发率。

Overview of the Current Issues and Advances in Haemopoietic Stem Cell Transplantation for β-thalassemia Major

Bone marrow transplantation (BMT) is the only possible curative treatment for β-thalassemia major. The largest experience occurred in Pesaro, Italy, where the BMT was applied after a standard risk assessment. The patients were divided into 3 risk classes based on liver size by physical examination, the presence or absence of fibrosis by liver biopsy, and adherence to regular iron chelation. Outcomes were mainly affected by the risk status. After modifications to the conditioning regimens, the risk of transplantation-related complications in highrisk recipients reduced considerably. As a result, outcomes after transplantation have become more similar across risk categories. For BMT, most centers use bone marrow instead of peripheral blood in thalassemia. Some studies showed that peripheral blood stem cell transplantation (PBSCT) is better than BMT with regard to hematologic recovery, hospitalization period, leukemia-free survival, overall survival (OS), and transplant-related mortality (TRM). No significant differences were seen in grade II to IV acute GVHD (aGVHD); but the incidence of chronic GVHD (cGVHD) was significantly higher in the PBSCT group. BMT from unrelated donors may offer similar results to those obtained using HLA-identical family donors, at least for patients who are not fully compliant with conventional treatment and do not yet show severe complications of iron overload. All studies conclude that MUD BMT might be a good alternative for patients with less risk factors. Another study concluded that, at present, due to high graft failure and GVHD rates, BMT from alternative donors should be restricted to patients who have poor life expectancies because they cannot receive adequate conventional treatment or because of alloimmunization to minor blood antigens. In another study unrelated cord blood transplantation (CBT) was compared to related donor transplantation for children with β-thalassemia. The results were comparable to the survival rates of related-donor BMT for thalassemia. It has always been a dream for parents to have a new baby who might be a donor for his/her sibling and save his/her life. Today some families tried to learn the HLA group of the fetus using prenatal diagnosis. The last step in this development was preimplantation genetic diagnosis (PGD). PGD has become available as an alternative to prenatal diagnosis in order to avoid the risk for pregnancy termination, because PGD allows selection of unaffected embryos before a pregnancy is established. Gene therapies, the ultimate idea, involves replacing allogeneic stem cell transplantation with the transfer of normal globin genes into patientderived autologous haematopoietic stem cells, bypassing the need for allogeneic donors and the immunosuppression required to achieve engraftment of the transplanted cells and to eliminate the risk of donor-related graft-versus-host disease. The successful preclinical studies in thalassaemia mousemodels, the accumulating data on lentiviral vector-mediated HSC transduction and the anticipated increased safety of lineage-restricted globin SIN lentiviral vectors strongly support the initiation of Phase I gene therapy clinical trials in β-thalassaemia.

Comparable Analysis of Outcomes for Allogeneic Peripheral Blood Stem Cell Transplantation from Matched Related and Matched Unrelated Donors in Acute Myeloid Leukemia

This study compared the results of allogeneic peripheral blood stem cell transplantation (PBSCT) from unrelated and related donors in 142 consecutive patients with acute myeloid leukemia (AML). The cumulative incidence of acute graft-versus-host disease (GVHD) was 37.6% in the related PBSCT group and 53.7% in the unrelated PBSCT group. The cumulative incidence of extensive chronic GVHD was also higher in the unrelated PBSCT group (19.5%) than in the related PBSCT group (8.9%). The overall survival rate at 4 years was 62.4 ± 5.4 and 53.8 ± 1.2% (p = 0.535) in the related and unrelated PBSCT group, respectively. In a multivariate analysis, unrelated PBSCT was identified as a risk factor for the development of extensive chronic GVHD (hazard ratio = 3.019, p = 0.027). Unfavorable cytogenetics and the disease status at the time of transplantation were found to be related to overall survival. In the case of high-risk AML, the survival rate and relapse incidence were significantly better in the matched unrelated PBSCT group (p = 0.047 and 0.039, respectively). In conclusion, the allogeneic PBSCT outcomes for AML were comparable in the matched related and matched unrelated groups. Nonetheless, for high-risk AML patients, matched unrelated PBSCT was found to be preferable to matched related PBSCT.

Comparison of stem cell sources in the severity of dry eye after allogeneic haematopoietic stem cell transplantation

AimsTo compare the incidence and severity of dry eye (DE) after allogeneic haematopoietic stem cell transplantation (HSCT) according to the stem cell source. The authors specifically focused on patients who...

Comparative Analysis of Outcomes of Allogeneic Peripheral Blood Stem Cell Transplantation From Related and Unrelated Donors.

Abstract 3381Poster Board III-269This study compared the results of allogeneic peripheral blood stem cell transplantation (PBSCT) from unrelated and related donors, and involved 235 consecutive patients from 10 centers who received an allogeneic PBSCT for hematological malignancies between Jan 2004 and Dec 2008. Among these patients, 160 (68.1%) received an HLA-matched related PBSCT and 75 (31.9%) a matched unrelated PBSCT. Sixty-five patients (27.7%) had a high-risk disease status at transplantation. The cumulative incidence of acute graft-versus-host disease (GVHD) was 43.9% for the related PBSCT group and 59.3% for the unrelated PBSCT group (P-value:0.011). Although the cumulative incidence of chronic GVHD was no different between the related (54.2%) and unrelated (64.9%; P-value:0.199) PBSCT groups, the cumulative incidence of extensive chronic GVHD was higher among the unrelated PBSCT group (34.9%) than among the related PBSCT group (17.0%; P-value:0.015). Plus, the unrelated PBSCT group showed a higher cumulative incidence of CMV infection (44.6%) than the related PBSCT group (26.8%; P-value:0.002). The overall survival rate at four-year was 58.2% versus 49.1% (p=0.698) and the cumulative incidence of relapse 28.4% versus 25.0% (P-value:0.289) for the related and unrelated PBSCT groups, respectively. Among the factors examined, unrelated PBSCT (P-value:0.024), the CD34-positive cell count (>6 × 106/kg; P-value:0.041), and CMV infection (P-value:0.066) were all related with a higher incidence of extensive chronic GVHD. However, in a multivariate analysis, only unrelated PBSCT was identified as a risk factor for the development of extensive chronic GVHD (hazard ratio=2.012, 95% confidence interval=1.006-4.023; P-value:0.048). In conclusion, the overall survival and relapse incidence were not significantly different between the related and unrelated PBSCT groups. However, a higher incidence of CMV infection and extensive chronic GVHD was observed in the unrelated PBSCT group. Disclosures:No relevant conflicts of interest to declare.

Donor Lymphocyte Infusions (DLI) After Peripheral Blood Stem Cell Transplantation. A Retrospective Analysis of 357 Patients by the Chronic Leukemias Working Party EBMT.

Abstract 3309Poster Board III-197Donor Lymphocyte Infusions (DLI) constitute a potent therapeutic option for treating relapse of chronic myelogenous leukemia (CML) after hematopoietic stem cell transplantation (SCT) inducing durable remissions in the majority of patients. A number of factors is known to influence the efficiency of DLI. A preliminary analysis of EBMT data had suggested that DLI efficiency might be inferior after peripheral blood stem cell transplantation (PBSCT) as compared to DLI following bone marrow transplantation (BMT) (Schmid et al. ASH, 2005). To control for a number of other factors that were not known at the time of the previous analysis, we repeated this analysis based on the results of 357 patients treated with DLI following PBSCT (N=108) and BMT (N=249). We limited the analysis to patients who relapsed after standard intensity conditioning SCT from HLA-identical family donors in first chronic phase of disease. The median age of patients was 39 years (range 18-60) with predominance of males (59%). 53% of patients with known data were CMV positive and in 44% of the patients there was a sex-mismatch with the stem cell donor. SCTs have been performed between 1994 and 2007 (median year: 1998) and the conditioning treatment included total body irradiation (TBI) in 68% and T cell depletion in 44% of patients. 92% of patients with known data achieved complete remission after SCT while grade II-IV acute GvHD occurred in 18% of patients and extensive chronic GvHD in 17% of patients. Median time to relapse was 17 months (range 0.6-129) and median time from SCT to first DLI infusion was 23 months (range 0.6-142). Looking at the patients with known data at the time of first DLI infusion, the relapse could be classified as molecular/cytogenetic in 63%, hematologic in 27% and transformed in 10% of patients. The median year of first DLI was 2000 ranging from 1995 to 2007. As the initial DLI infusion, 9% of patients received <1×10e6, 62% 1.1-10×10e6 and 29% received >10×10e6 CD3+ cells/kg. However, the comparative analysis of groups based on the stem cell source revealed that the group of patients transplanted with PBSCs included significantly more males (68 vs. 56%), were older (median age 42 vs. 39) and underwent more frequently T cell depletion at SCT (72 vs. 34%,). PBSCTs have been performed more recently (median year 1999 vs. 1997) and both duration of remission and time from SCT to first DLI were shorter after PBSCT (median duration: 12 vs. 21 months and 14 vs. 26 months respectively). The initial cell dose in patients from PBSCT arm was significantly lower than in BMT group (≤10×10e6 CD3+/kg in 89% vs. 65% of patients). Similarly to the previous study, we also observed a trend towards superior overall survival after DLI in BMT group compared to PBSCT group, especially in the early post-transplant period. The actuarial probability of survival at five years from DLI was 77% in PBSCT group and 79% in BMT group. However the differences were not statistically significant (p=0.77). The source of stem cells did not influence the occurrence of molecular/cytogenetic remissions after DLI (80% vs. 77%) grade II-IV acute GVHD (16% vs. 16%), chronic GVHD (23% vs. 30%) and myelosuppression (10% vs. 16%). In order to search for factors having impact on survival of analyzed patients, we performed both univariate and multivariate survival analyses. The univariate analysis revealed that interval from SCT to DLI longer than 2 years (p=0.001), date of DLI after 2000 (p=0.026) and molecular/cytogenetic stage of relapse at DLI (p<0.001) were associated with favorable survival. Similarly, the multivariate Cox analysis identified interval between SCT and DLI (HR= 0.50, CI: 0.3-0.8; p=0.01 for after 2 years), date of DLI (HR=0.63, CI:0.4-1.0; p=0.07 for after 1999), and stage of relapse (HR=2.8, CI:1.2-6.5; p=0.02 for HemCR and HR=3.6, CI:1.8-7.0; p<0.001 for missing data group), but not for stem cell source (HR=0.95, CI 0.56-1.6 ;p=0.86) as independent factors affecting survival. Based on our retrospective data from EBMT registry covering a period of 14 years of SCT and DLI, it seems that the PBSCT does not affect the efficiency of DLI compared to BMT. Therefore, keeping all limitations of a retrospective analysis in mind, it seems that differences in efficacy of DLI do not influence the decision whether PBSC or BM should be used as stem cell source for allogeneic SCT in CML in first chronic phase. DisclosuresNo relevant conflicts of interest to declare.

Efficacy of the BEACOPP regimen in refractory and relapsed Hodgkinlymphoma

The BEACOPP regimen is a consolidated first-line treatment regimen for advanced stage Hodgkin lymphoma (HL), while few data are available on the efficacy of this regimen in advanced disease. About 50% of patients with HL relapsed after or refractory to first-line therapy achieve a durable response after peripheral blood stem cell transplantation (PBSCT). Patients relapsing after a PBSCT (performed as second line therapy) have a very poor prognosis. We evaluated the efficacy of BEACOPP in two settings: patients refractory or in relapse after first-line therapy (Group A) and patients relapsing after a PBSCT (Group B). Twenty-three patients with HL, admitted between February 2003 and April 2007, were retrospectively studied: 10 patients in Group A and 13 in Group B. Group A: Nine complete remissions (CR) and one partial remission (PR) were achieved following BEACOPP treatment. After a median follow-up of 32 months, one patient has died due to secondary leukemia, while the other eight are alive, five (50%) in second CR, three in third CR after PBSCT and one with disease. Group B: Eight of the 13 patients (62%) obtained a CR, one patient a PR, two were refractory and two have died of toxicity. To date, eight patients (62%) are alive, four (31%) still in CR. All patients experienced hematologic toxicity (WHO 3–4) with two deaths due to septic shock. These results show that BEACOPP is an effective regimen for both refractory/relapsed patients with HL after first-line treatment (Group A) and for patients relapsing after a PBSCT (Group B) with a 3-year probability of overall survival, progression-free survival, and cumulative incidence of relapse of 90, 50, and 33.3% in Group A, and 61, 31, and 37.5% in Group B, respectively.

Peripheral Blood versus Bone Marrow as a Source of Hematopoietic Stem Cells for Allogeneic Transplantation in Children With Class I and II Beta Thalassemia Major

Peripheral blood stem cell transplantation (PBSCT) has been extended to treating hematologic disorders, but the benefits over bone marrow transplantation (BMT) still remain unclear, especially in nonmalignant hematologic disorders. In this study, we compared class I-II thalassemic children who underwent HLA-matched PBSCT and BMT for treatment. Conditioning regimens consisted of busulfan and cyclophosphamide, followed by cyclosporine ± methotrexate for graft-versus-host disease (GVHD) prophylaxis. Using multivariate analysis, the outcomes of 87 PBSCT patients and 96 BMT patients were reported (median follow-up: 29 and 60 months, respectively). The median time to neutrophil and platelet recovery in PBSCT patients (11 and 18 days, respectively) was significantly lower than BMT patients (19 and 26 days, respectively) ( P < .001). Grade II-IV acute GVHD was more frequent in PBSCT versus BMT group (72% versus 55%; P = .003) (relative risk = 1.75, 95% confidence interval [CI]: 1.20-2.57). The incidence of chronic GVHD was more frequent in the PBSCT versus BMT group (48% versus 19%; P < .001) (relative risk = 2.62, 95% CI: 1.43-4.82). There was no difference in the 2-year overall survival after PBSCT and BMT (83% and 89%, respectively). The 2-year disease-free survival was 76% in both groups. These results show some advantages of PBSCT, but to improve the risk of GVHD in PBSCT, a better conditioning and prophylaxis regimen is needed.

Clinical Outcomes and the Impact of Anti-Thymocyte Globulin (ATG) and Chronic Graft Versus Host Disease (cGVHD) Following Pediatric Allogeneic Stem Cell Transplantation: A Comparison between Peripheral Blood and Bone Marrow as a Source of Stem Cells.

INTRODUCTION: The use of peripheral blood as a source of stem cells for pediatric allogeneic stem cell transplantation remains controversial. We present a retrospective analysis evaluating the safety and efficacy of allogeneic peripheral blood stem cell transplantation (PBSCT) compared to allogeneic bone marrow transplantation (BMT) for the treatment of acute leukemia at our centre. The impact of ATG added to the treatment regimen was also evaluated in this analysis.METHODS: A chart review was conducted on all pediatric patients who underwent an allogeneic stem cell transplant for acute leukemia between April 1991 and August 2003 at the Alberta Children's Hospital. All patients who received stem cells from HLA matched or one-antigen mismatched donors were included in this analysis. Data were analyzed using SPSS.RESULTS: 85 children (ages 9 months to 17 years) met study criteria. 24 patients underwent a PBSCT while 61 patients, a BMT for the treatment of either ALL (n=54) or AML/MDS (n=31). Median follow up time was 5.9 years. Six of 24 patients in the PBSCT group, and 30 of the 61 patients in the BMT group received ATG (p=.042). There was a trend towards increased overall survival (OS) at 5 years following PBSCT (p=.078). Disease free survival (DFS) at 5 years following PBSCT and BMT was similar (p=.297). Subgroup analysis found no difference in OS or DFS between PBSCT and BMT in patients receiving (p=.221, p=.820) or not receiving ATG as part of the conditioning regimen (p=.448, p=.820). Chronic GVHD was increased following PBSCT (45.8%) compared to BMT (19.7%) (p=.015). The rate of severe cGVHD, however, was not significantly different (25% vs. 11.5% for PBSCT and BMT, p=.119) between the two groups. No patients receiving ATG prior to PBSCT developed cGVHD (p=.009). Addition of ATG to the transplant regimen had no impact on the rate of cGVHD following BMT (p=.221). There was no increase in mortality due to cGVHD following PBSCT (p=.243) or BMT (p=.865). Although, there was a trend to improved DFS in patients who developed cGVHD following PBSCT, this was not statistically significant (p=.057). Despite a statistically significant increase in TRM found in all patients with cGVHD at one year post-transplantation (p=.048), there was no difference in TRM between the PBSCT (4.2%) and BMT (14.8%) groups (p=.173).CONCLUSION: Allogeneic PBSCT is a safe and effective alternative to allogeneic BMT for the treatment of acute leukemia in the pediatric population. Although there is an increased rate of cGVHD following PBSCT this does not appear to influence OS, DFS or TRM in our analysis. Addition of ATG into the transplant regimen decreases the occurrence of cGVHD after PBSCT. Studies to further assess the role of ATG in PBSCT are warranted.

Donor Lymphocyte Transfusion (DLT) in the Treatment of Relapsed CML after Allogeneic PBSCT - A Retrospective Analysis of 346 Patients by the EBMT Chronic Leukemia Working Party.

DLT has become the gold standard for the treatment of reccurrent CML after allogeneic stem cell transplantation. However, so far, published data are based on DLT following bone marrow transplantation (BMT). During recent years, mobilized peripheral blood stem cell transplantation (PBSCT) have been increasingly performed. To evaluate the efficacy of DLT following PBSCT, we retrospectively analysed the results of 86 patients treated with DLT for CML relapse after PBSCT from HLA-identical family donors. Results were compared to 260 patients receiving DLT for relapse after related BMT. Reduced intensity transplants were excluded.BMT and PBSCT groups were balanced in terms of patient age (median: 40 vs 42 y), conditioning, stage at transplant (84% vs 76% in first chronic phase (CP) p=.2), and stage at relapse (molecular/cytogenetic: 59% both, CP: 28% vs 20%, advanced: 13% vs 21%, p=.2). However, BMT patients had been transplanted in earlier years (median: 1994 vs.1998, p<.001), had a longer remission after transplantation (median: 677 vs. 275 d, p<.001), and had experienced more aGvHD after transplantation (58% vs. 34%, p<.001). Complete molecular or cytogentic remission was achieved in 71% of the patients, with a trend towards better response in BMT recipients (p=.06). Overall (OS) and event free survival (EFS) at five years from DLT are shown in table 1. Outcome was significantly superior in BMT recipients, in particular if DLT was given for hematological, rather than cytogenetic or molecular relapse. In a cox regression model, four factors were associated with better OS/EFS: Transplantation in CP1 (p<.001/.002), early stage at relapse (molecular/cytogenetic vs. hematological, p<.00/<.001), a longer remission after transplantation (p=.005/.028), and BM vs. PBSC for transplantation (p= .003/.004). In contrast, age of patient and donor, acute or chronic GvHD after transplantation, the use of chemotherapy or imatinib before DLT, and the initial number of transfused CD3+ cells were not significant.The results of this retrospective study suggest a reduced efficacy of DLT in CML relapse following related allogeneic PBSCT as compared to BMT. This effect seems to be independent from established risk factors as disease stage and remission duration. However, since several adverse factors are not equally distributed among the two groups, a bias might be induced, although no statistically significant imbalance could be detected. Therefore, the observation needs to be confirmed in a larger cohort or a prospective study.Table 1Outcome after DLTNoBMTPBSCTpTotal34626086OS at five years from DLT71%75%66%< .001EFS at five years from DLT61%64%41%< . 001

Allogeneic versus autologous versus peripheral stem cell transplantation in CR1 pediatric AML patients: A single center experience

Treatment of childhood acute myelocytic leukemia (AML) in first remission, is still evolving. Allogeneic bone marrow transplantation (BMT) in patients with a donor has been well established, but the role of autologous transplantation remains of interest, particularly in the light of some encouraging results in adults. Out of 81 pediatric patients with AML in first CR, 67 were biologically randomized for allogeneic (n = 31), autologous (n = 20), or peripheral stem cell transplant (n = 16) after completing consolidation treatment, with the remaining (n = 11) dropping out or receiving chemotherapy. Disease free survival (DFS) of these different groups were analyzed. Allogeneic transplantation is not superior to autologous and autologous peripheral blood stem cell transplantation (PBSCT) (DFS in 5 years is 61%, 50%, and 75%). The 5 years DFS in the autologous PBSCT group is significantly better than in the autologous BMT group (75% vs. 50%, P < 0.05). In pediatric AML patients without a donor, autologous BMT or autologous PBSCT appears to be an effective treatment option with low transplant related mortality especially in less privileged countries where the chemotherapy only results are still low.

The Post-Transplant Day 30 Lymphocyte Count Strongly Correlates with Transplanted Cd34 Dose and Is Predictive for Minimal Residual Disease and Mortality in Patients with Cml Undergoing Allogeneic Stem Cell Transplants from Matched Siblings.

Between 12/1993 and 5/2004, 80 patients with chronic myeloid leukemia (CML) received a T cell depleted stem cell transplant from an HLA identical sibling, with delayed add-back of donor T cells on days 30–45 and again on day 60–100 for patients not developing ≥ grade II acute GVHD. Four transplant regimens were evaluated (1) total body irradiation (TBI) + cyclophosphamide (Cy) and standard dose (SD) cyclosporine (CSA) + bone marrow transplantation (BMT) (N=25); (2) TBI + Cy + SD-CSA + peripheral blood stem cell transplantation (PBSCT) (N=16); (3) TBI + Cy + PBSCT and low dose or no (LD/N) CSA (N=22); (4) TBI + fludarabine (Flu) + Cy and LD/N CSA (N=17). Median CD34 and CD3 doses were 4.5 x 106/kg and 0.75 x 105/kg respectively Prior to transplantation 54 patients had chronic phase (CP) and 26 had more advanced CML. Kaplan-Meier survival plots were created for overall survival, current disease free survival (DFS); and transplant-related mortality (TRM). Outcomes were analyzed using log rank tests. The outcomes for chronic versus more advanced CML were respectively 85±5% vs 36±10%, p=<0.0001 for overall survival; 13±5% vs 42±11%, p<0.01 for TRM; 76±6% vs 33.5±9% p=<0.0001 for current DFS (figure). Of patients in CP, 22/48 were negative for BCR/ABL at 3 months post transplant, increasing to 35/46 at 12 months, and 42/46 are currently disease free. Factors affecting outcome in 54 CP patients were (1) source of transplant: there was a survival benefit for the PBSCT group compared to BMT recipients (p=0.03). and (2) Day 30 lymphocyte count (LC30): there was a higher survival and lower TRM for patients with a count above the median of 300/μl: 100 vs 70±9%; p=0.003; 0 vs 26±8%, p=0.006 respectively. Similar differences were observed in the PBSCT. Molecular response (PCR for BCR/ABL negative at 3, 6, 12 and months) was also highly correlated with higher LC30 at all time points (p=<0.0001; <0.0001; 0.0004 respectively). (3) CD34 dose above the median dose of 4.5 x 106/kg in 28 CP patients was associated with 100% survival and zero TRM vs 69±9% and 27±9% for 26 patients below the median; p=0.002 and 0.003 respectively). Higher than median CD34 doses significantly correlated with molecular response at 3, 6 months. (p=<0.0001; <0.0001 respectively). Higher CD34 dose also correlated significantly with higher LC30 (p= 0.03) (figure). These results show that T cell depleted SCT for CML CP results in favorable long-term survival with low TRM. Results for more advanced disease were complicated by high relapse and TRM but showed the same improved outcome with higher CD34 doses. The results highlight a predictive importance for LC30, not only for TRM, but also for a graft versus leukemia effect. Since LC30 was highly correlated with CD34 dose, our results suggest that transplant outcome in T depleted CML allografts can be improved by transplanting more than 4.5 x 106 CD34 cells/kg. [Display omitted]

Superior survival in primary systemic amyloidosis patients undergoing peripheral blood stem cell transplantation: a case-control study

AbstractPrimary systemic amyloidosis (AL) is a plasma cell dyscrasia resulting in multisystem failure and death. High-dose chemotherapy with peripheral blood stem cell transplantation (PBSCT) has been associated with higher response rates and seemingly higher overall survival than standard chemotherapy. Selection bias, however, confounds interpretation of these results. We performed a case-match-control study comparing overall survival of 63 AL patients undergoing transplantation with 63 patients not undergoing transplantation. Matching criteria included age, sex, time to presentation, left ventricular ejection fraction, serum creatinine, septal thickness, nerve involvement, 24-hour urine protein, and serum alkaline phosphatase. According to design, there was no difference between the groups with respect to sex (57% males), age (median, 53 years), left ventricular ejection fraction (65%), number of patients with peripheral nerve involvement (17%), cardiac interventricular septal wall thickness (12 mm), serum creatinine (1.1 mg/dL [97.24 μmol/L]), and bone marrow plasmacytosis (8%). Sixty-six patients have died (16 cases and 50 controls). For PBSCT and control groups, respectively, the 1-, 2-, and 4-year overall survival rates are 89% and 71%; 81% and 55%; and 71% and 41%. Outside a randomized clinical trial, these results present the strongest data supporting the role of PBSCT in selected patients with AL.

Reassessing autotransplantation for acute myeloid leukaemia in first remission – a matched pair analysis of autologous marrow vs peripheral blood stem cells

The role of autologous stem cell transplantation in adult patients with acute myeloid leukaemia (AML) in first remission is unclear, yet it has become standard treatment for myeloma and this paper explores whether the source of transplanted stem cells may explain this paradox. In total, 57 patients from the Royal Marsden Hospital who received an unpurged bone marrow transplant (ABMT) were matched with 114 patients from the EBMT registry who had undergone peripheral blood stem cell transplantation (PBSCT). Patients were matched for karyotype, FAB type, remission-autograft interval and age. In the PBSCT group, haematopoietic recovery was significantly faster and nonrelapse mortality at 4 years was significantly lower (13 vs 1%, P=0.04). The relapse rate and overall survival at 4 years (20 vs 31% and 77 vs 63%) were also better with PBSCT, although the differences were not statistically significant. Autografting should be reassessed in a randomised trial for first remission AML patients using peripheral blood as a source of stem cells rather than bone marrow.

Outcome of transplantation of highly purified peripheral blood CD34+ cells with T-cell add-back compared with unmanipulated bone marrow or peripheral blood stem cells from HLA-identical sibling donors in patients with first chronic phase chronic myeloid leukemia

Outcomes of highly purified CD34(+) peripheral blood stem cell transplantation (PBSCT) for chronic phase chronic myeloid leukemia (CML) (n = 32) were compared with those of PBSCT (n = 19) and of bone marrow transplantation (BMT) (n = 22) in the HLA-compatible sibling donor setting. Median follow-up was 18 months after CD34(+)-PBSCT and unmanipulated PBSCT and 20 months after BMT. CD34(+)-PBSCT was associated with delayed T-cell immune reconstitution at 3 months and 12 months after transplantation compared with PBSCT (P <.001) or BMT (not significant [NS]). The estimated probability of grades II to IV acute graft-versus-host disease (GVHD) was 60% +/- 13% for the PBSCT group, 37% +/- 13% for the BMT group, and only 14% +/- 8% for the CD34(+)-PBSCT group (CD34-PBSCT versus BMT, P <.01; and CD34-PBSCT versus PBSCT, P <.001). The probabilities for molecular relapse were 88% for CD34(+)-PBSCT, 55% after BMT, and 37% after PBSCT (CD34(+)-PBSCT versus PBSCT, P <.03). Cytogenetic relapse probability was 58% after CD34(+)-PBSCT, 42% after BMT, and 28% after PBSCT (NS). After CD34(+)-PBSCT, 26 of 32 patients received a T-cell add-back. Hematologic relapse occurred in 4 of 22 patients after BMT, in 3 of 19 patients after PBSCT, and in only 1 of 32 patients after CD34(+)-PBSCT. The occurrence of a hematologic relapse in patients receiving CD34(+)-PBSC transplants was prevented by donor leukocyte infusions, which were applied at a median of 4 times (range, 1-7 times) with a median T-cell dose of 3.3 x 10(6) x kg/body weight [at a median] beginning at day 120 (range, 60-690 days). The estimated probability of 3-year survival after transplantation was 90% in the CD34(+)-PBSCT group, 68% in the PBSCT group, and 63% in the BMT group (CD34-PBSCT versus BMT, P <.01; and CD34-PBSCT versus PBSCT, P <.03). Transplantation of CD34(+)-PBSCs with T-cell add-back for patients with CML in first chronic phase seems to be safe and is an encouraging alternative transplant procedure to BMT or PBSCT.

Hematopoietic and immune recovery after allogeneic peripheral blood stem cell transplantation and bone marrow transplantation in a pediatric population.

To compare the hematopoietic and immune recoveries after allogeneic transplantation with different cell sources, we analyzed the recovery patterns of blood components after allogeneic peripheral blood stem cell transplantation (PBSCT) in comparison with that after allogeneic bone marrow transplantation (BMT) in a pediatric population. Sixteen patients received PBSCT, and 24 received BMT between January, 1995 and March, 2000. The patients had acute lymphoblastic leukemia (ALL; n = 22), acute myelogenous leukemia (AML; n = 8), myelodysplastic syndrome (MDS; n = 3), or other diseases (n = 7). The median ages of patients in the PBSCT and BMT groups were 9 yr and 6 yr, respectively. Cyclosporin A (CsA) plus methotrexate or methylprednisolone was used as a graft-vs.-host disease (GvHD) prophylaxis regimen in the PBSCT group, whereas CsA alone or methotrexate alone was used in the BMT group. Circulating lymphocyte numbers and subpopulations determined by flow cytometric analysis were used as markers of immune recovery. In the PBSCT group, the median number of harvested CD34+ cells was 7.25 (range: 1.3-27.6) x 106/kg of the recipient's body weight, while the median number of harvested nucleated cells was 4.7 (range: 3.7-10.5) x 108/kg. All of the patients were engrafted. Myeloid engraftment occurred sooner after PBSCT than after BMT (median number of days to achieve absolute neutrophil counts (ANC) > 0.5 x 109/L; 11 and 15, respectively; p < 0.0001) and similar results were found for platelet engraftment (median number of days to achieve a platelet count of > 20 x 109/L; 12 and 21, respectively; p = 0.004). On the other hand, after PBSCT the absolute numbers of total circulating lymphocytes and lymphocyte subpopulations were not significantly different from those after BMT. The incidence of acute GvHD after PBSCT was the same as that after BMT, while chronic GvHD developed more frequently after PBSCT than after BMT (p = 0.005). In a pediatric population, the indications for PBSCT and BMT should be based on these findings in addition to regard for the donor's safety.