Hematopoietic stem cell transplantation for hematological malignancies in Europe

Allogeneic hemopoietic stem cell transplantation in solid tumors

The existence of a graft versus tumor (GVT) effect of donor-derived T cells after allogeneic hematopoietic stem cell transplantation is well established as a critical component for the success of the procedure in several hematologic malignancies. Although it has been suggested that a GVT effect might also be generated in patients affected by refractory solid tumors, the morbidity of conventional allogeneic hematopoietic stem cell transplantation has limited its investigation in these diseases. Recently introduced allogeneic nonmyeloablative regimens have greatly decreased morbidity and mortality related to transplants which retain a powerful GVT. On this basis, it has become possible to explore the existence of alloreactivity toward solid tumors. The present article reviews the early clinical results of this novel immunotherapeutic approach for solid tumors.

Stem-cell transplantation in multiple myeloma

In patient with newly diagnosed multiple myeloma (MM), randomized studies have shown that autologous stem-cell transplantation (ASCT) is superior to conventional chemotherapy, and ASCT is now standard care, at least for younger patients. The best conditioning regimen is melphalan 200 mg/m2, and the best stem-cell source is unselected peripheral progenitor cells. Recent results of the IFM94 trial show that double ASCT is superior to single ASCT, at least in patients who do not achieve a 90% response after one transplant. By combining biologic markers (beta2-microglobulin, albumin) and genetic markers (hypodiploidy, chromosome 13 deletion) it is possible to accurately predict prognosis after ASCT. The results of allogeneic SCT remain disappointing due to a high transplant mortality. Strategies combining ASCT and reduced-intensity allogeneic SCT are currently being studied.

Cost of autologous peripheral blood stem cell transplantation: the Norwegian experience from a multicenter cost study

High-dose therapy with autologous blood progenitor cell support is now routinely used for patients with certain malignant lymphomas and multiple myeloma. We performed a prospective cost analysis of the mobilization, harvesting and cryopreservation phases and the high-dose therapy with stem cell reinfusion and hospitalization phases. In total, 40 consecutive patients were studied at four different university hospitals between 1999 and 2001. Data on direct costs were obtained on a daily basis. Data on indirect costs were allocated to the specific patient based on estimates of relevant department costs (ie the service department's costs), and by means of predefined allocation keys. All cost data were calculated at 2001 prices. The mean total costs for the two phases were US$ 32,160 (range US$ 19,092-50,550). The mean total length of hospital stay for two phases was 31 days (range 27-37). A large part of the actual cost in the harvest phase was attributed to stem cell mobilization, including growth factors, harvesting and cryopreservation. In the high-dose chemotherapy phase, the most significant part of the costs was nursing staff. Average total costs were considerably higher than actual DRG-based reimbursement from the government, indicating that the treatment of these patients was heavily subsidized by the basic hospital grants.

Patient-rated emotional and physical functioning among hematologic cancer patients during hospitalization for stem-cell transplantation

In this 3-year prospective inpatient study, 220 patients received stem-cell transplantation (SCT) for hematologic cancer at a single institution. The objective of the study is to provide data on patient-rated emotional (depression and anxiety) and physical (overall physical status, energy level, and systemic symptomatology) functioning during hospitalization for SCT and to compare whether these differ between autologous and allogeneic SCT. Patients were assessed at hospital admission (T1), day of SCT (T2), and 7 days (T3) and 14 days (T4) after SCT, yielding a total of 852 evaluations. For the overall sample, anxiety was highest at T1 and decreased afterwards; a marked worsening in physical health status variables corresponded with a sharp increase in depression from T1 to T3, and was followed by an improvement in physical health and a reduction of depression. Compared to allogeneic SCT, a better physical outcome for autologous SCT was demonstrated by the significant group effect for systemic symptomatology and by the significant group x time interaction for overall physical status and energy level; there were no significant differences in depression or anxiety between SCT groups. These findings have implications for treatment decision making, coping with the transplantation process, and improving prevention and treatment strategies.

Successful mobilization of peripheral blood stem cells using recombinant human stem cell factor in heavily pretreated patients who have failed a previous attempt with a granulocyte colony-stimulating factor-based regimen

To assess the efficacy of recombinant human stem cell factor (rHuSCF), 48 patients who had failed to mobilize >2.0 x 10(6) CD34+ cells/kg with granulocyte colony-stimulating factor (G-CSF) (10 microg/kg twice daily) with, or without, concomitant chemotherapy (G-CSF-based regimen), were remobilized with the addition of rHuSCF (20 microg/kg/day). In all, 18/48 (38%) achieved a total of >2.0 x 10(6) CD34+ cells/kg with the second rHuSCF-based mobilisation alone and 29/48 (60%) achieved a cumulative total of >2.0 x 10(6) CD34+ cells/kg following remobilization. Inclusion of chemotherapy in the mobilization regimen resulted in a higher yield of CD34+ cells/kg for both the initial G-CSF-based and subsequent rHuSCF-based regimens (0.90 vs 0.54, P < 0.01 and 2.36 vs 1.34, P < 0.01, respectively). The total peripheral blood stem cells PBSC collected from the G-CSF-based regimen, performance status, baseline platelet count and albumin were significantly associated with successful remobilization. Patients with multiple myeloma were also more likely to successfully remobilize. There was no threshold of total collected from the failed G-CSF-based regimen below which successful remobilization with the rHuSCF-based regimen was not possible. We therefore propose a predictive model [PBSC expected = 0.6+(G-CSF-based total collection)+2 (rHuSCF-based day 1 collection)] to calculate the cumulative total of PBSC expected following a maximum of five leukaphereses. This algorithm may permit the early identification of patients who are unlikely to achieve sufficient PBSC for transplantation and allow physicians to direct the resources involved in PBSC collection in a more appropriate and economical manner.

rhG-CSF does not affect the phenotype of adult donor peripheral blood NK cells

Considerable evidence in preclinical models as well as in human transplantation now suggests that donor-derived natural killer (NK) cells can contribute to alloimmune recognition of recipient residual tumour cells. This makes the NK cell population an attractive target for in vitro or in vivo manipulations, in order to improve the antitumour effect of allogeneic transplantation. However, conditions in which allogeneic donor cells are collected vary; several reports have emphasised the different phenotypic and functional properties of T cells derived from marrow, cord blood or mobilised peripheral blood grafts; others have demonstrated different clinical outcomes following blood or marrow transplantation after myeloablative conditioning regimens. NK cells have been examined in this setting; the availability of new tools to study the expression of a variety of surface antigens that are involved in the control of NK cell activity offered us an opportunity to extensively characterise the phenotypic properties of NK cells from donors, before and after administration of pharmacological doses of rhG-CSF used for haematopoietic progenitor mobilisation. Our study suggests that rhG-CSF does not reproducibly alter blood NK cell phenotype in normal individuals, and thus that donor-derived cells are fully equipped to exert their potential antitumour effect.

Clinical experience with the delivery of thawed and washed autologous blood cells, with an automated closed fluid management device: CytoMate

BACKGROUND

Washing out of thawed autologous grafts, before reinfusion in poor-prognosis cancer patients who undergo high-dose chemotherapy, is desirable. The procedure allows for the reduction of infused dimethyl sulfoxide (DMSO) quantities and the performance of biologic controls on the infused cell product.

STUDY DESIGN AND METHODS

Three-hundred four patients were treated with intensified chemotherapy and autologous transplantation at a single institution. Fifty-four of them received washed cell products, because three or more bags were to be reinfused. The recently available, closed, automated, and current good manufacturing practice-compliant device (CytoMate, Baxter Oncology) was used for this purpose.

RESULTS

The performances of the device were similar to previously reported results, with greater than 75 percent CD34+ cell recovery. Neutrophil and platelet (PLT) recoveries were similar in the group of patients receiving washed cells and in the group of patients for whom cell products were extemporaneously thawed at the bedside. Adverse events that are typically reported after DMSO infusion were significantly less frequent and less severe in patients who received washed cells. Finally, the nurse staff on the transplant ward reported a decreased workload and more satisfactory procedure when infusing washed cell products.

CONCLUSION

The CytoMate device allows for a significant reduction in DMSO infusion, with a diminished frequency and severity of immediate side effects and does not compromise neutrophil or PLT engraftment.

Life-threatening graft-vs-host disease

Hematopoietic stem cell transplant (SCT) is considered standard therapy for a variety of malignant and nonmalignant diseases. Graft-versus-host disease (GVHD) still represents today a major complication of hematopoietic SCT. Two types of GVHD have traditionally been recognized on the basis of the time of onset following transplantation, distinct pathobiological pathways, and different clinical presentations. The acute form commonly breaks out 2 to 6 weeks after transplantation, affecting up to 60% of patients receiving allogeneic transplants from HLA identical donors. Transfer of immunocompetent donor T cells contained in the graft may undergo alloreactivity against recipient cells because of major or minor histocompatibility antigens disparities between the donor and the immunosuppressed host. Target specificity in acute GVHD involves preferential injury to epithelial surfaces of the skin and mucous membranes, biliary ducts of the liver, and crypts of the intestinal tract. Chronic GVHD affects approximately 30% to 80% of patients surviving 6 months or longer after stem cell transplantation and is the leading cause of nonrelapse deaths occurring more than 2 years after transplantation. Chronic GVHD is a multiorgan syndrome with clinical features suggesting some autoimmune diseases, and possibly both alloreactive and autoreactive T cell clones are involved in its pathophysiology. Although GVHD may convey beneficial graft-versus-leukemia/lymphoma effects, it also entails a significant risk of morbidity and mortality. Patients with mild GVHD need only minimal, if any, immunosuppressive treatment, whereas prognosis of patients with extensive disease or resistant to standard immunosuppressive treatment may be dismal. Early recognition of GVHD followed by prompt therapeutic intervention may prevent the progression to higher-grade disease and improve the outcome for patients receiving hematopoietic SCT.

Quality of life in adult hematopoietic cell transplant patients at least 5 yr after treatment: a comparison with healthy controls

BACKGROUND AND OBJECTIVE

As long-term survivors of hematopoietic cell transplantation (HCT) become more numerous, studies addressing the issue of long-term follow-up are necessary. In this study, we report on the quality of life (QOL) of HCT-patients, who were alive at least at 5 yr after transplantation in comparison to an age- and sex-matched sample of healthy controls assessed in the same time-period and the same geographical region.

DESIGN AND METHODS

The European Group of Research and Treatment of Cancer (EORTC)-QOL Questionnaire (EORTC-QLQ C30) was sent by post to 39 HCT-survivors. Thirty-four patients answered the questionnaire. Patients were compared with 68 healthy controls from the same geographical region. Patients and controls completed the EORTC in the same time period.

RESULTS

Mann-Whitney U-tests identified significantly lower QOL on the dimensions of physical and social functioning and on the financial impact symptom scale.

CONCLUSIONS

Patients who had survived their HCT for more than 5 yr did generally well in terms of global QOL. This is consistent with Kiss et al. (J Clin Oncol 2002;20:2334-2343), who found that chronic myeloid leukemia patients who were alive at least 10 yr after HCT report lower physical functioning in comparison to healthy controls. Problems in the areas of social functioning and financial difficulty can possibly be addressed by intensive rehabilitation processes integrating patients, family members and significant others. Interdisciplinary (medical, psychological and social) treatment of patients should not come to an end after the acute phase of the illness but should continue during check-ups following transplantation.

A multifactorial analysis of umbilical cord blood, adult bone marrow and mobilized peripheral blood progenitors using the improved ML-IC assay

OBJECTIVE

Assays that can evaluate the potential of individual human hematopoietic stem cells (HSC) are still lacking. We previously developed the myeloid-lymphoid initiating cell (ML-IC) assay that enumerates single CD34(+) cells that generate long-term culture-initiating (LTC-IC) and NK-initiating (NK-IC) daughter cells, or single primitive progenitors with multilineage potential. When transplanted in vivo, umbilical cord blood (UCB) has greater repopulating ability than bone marrow (BM) or mobilized peripheral blood (MPB). Whether the greater in vivo repopulating ability is due to an increased frequency of HSC in UCB and generative potential of UCB, BM, and MPB CD34(+) cells is not known.

MATERIALS AND METHODS

Single UCB, BM, and MPB CD34(+)CD38(-)Lin(-) or CD34(+)CD38(-)CD33(-) cells were plated in ML-IC assay and after 2 to 4 weeks, progeny was evaluated for frequency and generative potential of ML-IC. We also tested whether the ML-IC assay could be used to define if increased numbers of primitive progenitors generated by different cytokines in expansion cultures are mediated by recruitment of quiescent cells or by increasing their generative potential.

RESULTS

The frequency of ML-IC in BM, UCB, and MPB was similar, but the generative potential of UCB ML-IC was significantly higher. Substitution of Flt3-L, SCF, and IL-7 with Flt3-L and thrombopoietin significantly increased the generative potential of ML-IC, whereas Flt3-L, SCF, and hyper-IL-6 increased both ML-IC frequency and generative potential.

CONCLUSION

The ML-IC assay demonstrates that the greater repopulating ability of UCB is due to the higher generative ability of HSC in UCB. Furthermore, the ML-IC assay can discriminate between cytokine-mediated expansion of hematopoietic progenitors by enhancing generation of immature daughter cells or by recruiting otherwise quiescent cells.

Leydig cell injury as a consequence of an acute graft-versus-host reaction

Hematopoietic stem cell transplantation (HSCT) is associated with significant posttransplantation gonadotoxicity. This deficit has been mainly attributed to pretransplantation conditioning, but lower sperm counts in humans also appear to be associated with graft-versus-host disease (GVHD) following allogeneic HSCT. However, the mechanisms leading to diminished spermatocyte levels during GVHD remain unknown. Here we demonstrate that injury to intratesticular cells occurs in unconditioned F1 mice following the infiltration of donor alloreactive T cells during an acute graft-versus-host reaction (GVHR). Using computer-aided quantitative microscopic morphometry we demonstrate that the nadir of Leydig cell volume density coincides with the peak of intratesticular infiltration by donor T cells. Injury to Leydig cells correlates with an intratesticular inflammatory response characterized by interferon-γ and tumor necrosis factor-α production. These results demonstrate impairment of testosterone-producing Leydig cells during a local alloresponse, thus representing a mechanism that contributes to gonadal insufficiency following allogeneic HSCT.

Autologous bone marrow transplantation as consolidation therapy in the treatment of adult patients under 60 years with acute myeloid leukaemia in first complete remission: a prospective randomized Dutch-Belgian Haemato-Oncology Co-operative Group (HOVON) and Swiss Group for Clinical Cancer Research (SAKK) trial

The question as to whether autologous stem cell transplantation (SCT) after consolidation chemotherapy improves the probability of survival of patients with acute myeloid leukaemia (AML) in first remission has not been settled. Here, we present the results of a phase III study conducted in newly diagnosed adult AML patients aged <60 years. Patients who had reached a complete remission (CR) after two courses of induction chemotherapy and who were not eligible for a human leucocyte antigen-matched sibling SCT (n = 130), were randomized after a third consolidation cycle of chemotherapy between high-dose cytotoxic treatment and autologous bone marrow transplantation or no further treatment. No significant differences in disease-free survival and overall survival were observed between the two treatment arms. A slightly better overall survival in the no further treatment arm was because of fewer deaths in the first CR and a significantly better overall survival after the first relapse. The results are discussed in relation to the generic problems of applying autologous transplantation and in the perspective of the limited statistical power of this and other previously published studies.

Transmission of donor illness by stem cell transplantation: should screening be different in older donors?

With increasing donor age, the potential of transmitting diseases from donor to recipient reaches new dimensions. Potentially transmittable diseases from donors include infections, congenital disorders, and acquired illnesses like autoimmune diseases or malignancies of hematological or nonhematological origin. While established nonmalignant or malignant diseases might be easy to discover, early-stage hematological diseases like CML, light-chain multiple myelomas, aleukemic leukemias, occult myelodysplastic syndromes and other malignant and nonmalignant diseases might not be detectable by routine screening but only by invasive, new and/or expensive diagnostic tests. In the following article, we propose recommendations for donor work-up, taking into consideration the age of the donors. In contrast to blood transfusions, stem cells from donors with abnormal findings might still be acceptable for HCT, when no other options are available and life expectancy is limited. This issue is discussed in detail in relation to the available donor and stem cell source. Finally, the recommendations presented here aim at harmonized worldwide work-up for donors to insure high standard quality.

Ancestim (recombinant human stem cell factor, SCF) in association with filgrastim does not enhance chemotherapy and/or growth factor-induced peripheral blood progenitor cell (PBPC) mobilization in patients with a prior insufficient PBPC collection

Up to a third of autologous transplantation candidates fail to mobilize hematopoietic progenitors into the peripheral blood with chemotherapy and/or growth factor treatment, thus requiring innovative mobilization strategies. In total, 20 cancer patients unable to provide adequate PBPC products after a previous mobilization attempt were treated with ancestim (20 microg/kg/day s.c.) and filgrastim (10 microg/kg/day s.c.). In 16 patients, the pre-study mobilization was with filgrastim alone. Eight patients underwent single large volume leukapheresis (LVL) and 12 multiple standard volume leukaphereses (SVL) in both mobilizations. Pairwise comparison of peripheral blood CD34(+) cell concentrations on the day of first leukapheresis failed to document synergism - median CD34(+)/microl of 3.2 (<0.1 to 15.4) and 4.5 (1-28.56) for the pre-study and on-study mobilizations (P = 0.79, sign test), and 4.2 (<0.1-15.4) and 5 (1-28.56), respectively, for the 16 patients previously mobilized with filgrastim alone (P = 1, sign test). The number of CD34(+) cells/kg collected per unit of blood volume (BV) processed was similar in both mobilizations - median 0.1 x 10(6)/kg/BV and 0.09 x 10(6)/kg/BV, respectively (P = 1, sign test). In this phase II study, the combination of ancestim and filgrastim did not allow adequate PBPC mobilization and collection in patients with a previous suboptimal PBPC collection.

Low incidence of infectious complications after nonmyeloablative compared with myeloablative allogeneic stem cell transplantation

Allogeneic stem cell transplantation (SCT) using a myeloablative (MA) conditioning regimen is limited to relatively young patients because of increased transplant-related mortality in elderly patients. Nonmyeloablative (NMA) conditioning regimens have been developed aiming to reduce transplant mortality. In this study, we set out to evaluate the post-transplant occurrence of infectious complications in recipients of grafts from human leukocyte antigen (HLA)-identical sibling donors treated with either NMA or MA conditioning regimens. Data of 78 consecutively treated patients were analyzed. An NMA conditioning regimen was used in 40 patients and an MA regimen in 38 patients. A significantly lower rate of episodes of febrile neutropenia (0% vs. 34%, P<0.01) and post-transplant Epstein-Barr virus reactivations (0% vs. 18%, P<0.05) was found in SCT recipients treated with an NMA conditioning regimen compared with an MA conditioning regimen. Furthermore, fewer invasive fungal infections (2% vs. 12%, not significant) were diagnosed in the NMA group. The incidence of cytomegalovirus (CMV) reactivations and bacterial infections was low in both groups (CMV reactivations: 13% in both groups; bacterial infections: 10% in the NMA group vs. 8% in the MA group), while CMV disease developed in only 1 patient. Overall, compared to our MA regimen, we found a very low rate of infectious complications after NMA SCT.

Haematopoietic stem cell transplantation (HSCT) in Europe 2002. Changes in indication and impact of team density. A report of the EBMT activity survey

This 2002 European Group for Blood and Marrow Transplantation (EBMT) activity survey concentrates on current status, increase and decrease in haematopoietic stem cell transplantation (HSCT) activity in Europe and investigates the association of transplant rates with team density. In 2002, there were 20 207 HSCT, 6915 allogeneic (34%), 13 292 autologous (66%) and 3947 additional re- or multiple transplants collected from 586 centres in 39 European countries. Main indications were leukaemias (6523 (32%; 76% allogeneic)); lymphomas (10 760 (53%; 92% autologous)); solid tumours (1913 (9%; 92% autologous)) and nonmalignant disorders (874 (4%; 92% allogeneic)). Compared to 2001, there were increases (>10%) for AML, ALL 1st CR, CML not 1st cP, MDS, SAA and CLL in allogeneic HSCT and for MDS, Ewing's sarcoma, soft-tissue sarcoma and ovarian cancer in autologous HSCT. Decreases (>10%) were observed in autologous HSCT for acute leukaemias beyond 1st CR, CML cP, glioma, breast cancer and lung cancer. Correlation of transplant rates (number of transplants per 10 million inhabitants) with team density (number of transplant teams per 10 million inhabitants) suggests different diffusion patterns for autologous compared to allogeneic HSCT. These data describe current practice for blood and marrow transplantation in Europe and give some hints about mechanisms involved in HSCT rates.

Incidence and specificity of HLA antibodies in multitransfused patients with acquired aplastic anemia

BACKGROUND

This study aimed to establish the prevalence and characteristics of anti-HLA in antibody acquired aplastic anemia patients following cessation of antithymocyte globulin therapy and to characterize antibody in terms of epitope specificity.

STUDY DESIGN AND METHODS

One hundred and fifty multitransfused, untransplanted patients from eight European centers were investigated by serologic methods.

RESULTS

Sixty-two percent were antibody positive. Eighteen HLA-Class-I-specific antibodies (15 IgG, 3 IgM) were identified in 13 patients; 13 antibodies were specific for HLA-A epitopes and 5 for HLA-B. Epitope analysis identified significant correlation between serum reactivity and amino acid substitutions associated with HLA-Class-I epitopes. An excess of antibodies to HLA-A1-associated cross-reactive groups was identified. There was no significant difference in antibody frequency in patients taking cyclosporine compared to those who were not.

CONCLUSION

Data suggested a contribution from B cell memory of alloantigens introduced during pregnancy. In some cases, antibody production continued many years after the last transfusion, and although the target varied between individual patients, the antibody to HLA was focused on a few specific Class I epitopes, the majority of which mapped to the HLA-A molecule.

Graft-versus-myeloma effect following antithymocyte globulin-based reduced intensity conditioning allogeneic stem cell transplantation

In all, 41 multiple myeloma (MM) patients received an antithymocyte globulin (ATG), fludarabine, and busulfan-based reduced intensity conditioning (RIC) for allogeneic stem cell transplantation (allo-SCT) from HLA-identical siblings. In total, 29 patients (70%) were in partial remission, one patient in complete remission, and 11 (27%) with progressive disease at the time of allo-SCT. Median time between diagnosis and allo-SCT was 24 months. The cumulative incidences of grade II-IV and grade III-IV acute graft-versus-host disease (GVHD) were 36% (95% CI, 21-51%) and 7% (95% CI, 2-20%), respectively. Overall, 10 patients developed limited chronic GVHD, whereas seven developed an extensive form (cumulative incidence, 41% (95% CI, 26-56%) at 2 years). With a median follow-up of 389 days, the overall cumulative incidence of transplant-related mortality (TRM) was 17% (95% CI, 6-28%). In all, 11 patients (27%) are in continuous complete remission, and the Kaplan-Meier estimates of overall survival (OS) and progression-free survival (PFS) at 2 years were 62% (95% CI, 47-76%) and 41% (95% CI, 23-62%), respectively. PFS and OS were significantly higher in patients with chronic GVHD as compared to patients without chronic GVHD (P=0.006 for PFS and P=0.01 for OS). Collectively, these data demonstrate that RIC allo-SCT can mediate a potentially curative graft-versus-myeloma effect with an acceptable incidence of toxicity and TRM.

High-dose chemotherapy using BEAM for tumor debulking without stem cell support followed by early allogeneic reduced intensity conditioning transplantation to induce a graft-versus-lymphoma effect in patients with high risk or refractory lymphoma

In patients with refractory lymphoma, we tested the hypothesis that high-dose chemotherapy (BEAM) without stem cell support followed by a reduced intensity (RIC) allogeneic transplant with fludarabine and 2 Gy TBI 28 days later results in tumor debulking and establishment of a graft vs lymphoma effect, with acceptable toxicity. In a pilot protocol we treated 10 patients, 22-62 (median 47) years of age with high-risk or refractory Hodgkin's or non-Hodgkin's lymphoma. Donors were HLA identical siblings (eight) or unrelated volunteers. None died during the neutropenic phase after BEAM which lasted up to the RIC HSCT. The duration of neutropenia was 31-43 (median 36) days. All patients engrafted and nine achieved CR. All developed acute GvHD (median grade III) and all patients at risk developed chronic GvHD. Three patients died of GvHD. One relapsed and six patients are in continuous CR 10-32 (median 15) months after HSCT. This approach appears feasible and results in a high response rate. Neutropenia duration is of concern. It remains to be tested whether separation of debulking chemotherapy and induction of allogeneic effects confers an advantage.

‘Agglutination and flocculation’ of stem cells collected by apheresis due to cryofibrinogen

Collection of peripheral stem cells by apheresis is a well-described process. Here, investigations concerning 'agglutination and flocculation' of stem cells collected from two patients are described. In both cases, cryoproteins were observed and cryofibrinogen was identified using high-resolution two-dimensional electrophoresis. In one case, peripheral stem cells were collected after a second course of mobilization, and the cells were immediately washed at 37 degrees C before being frozen, allowing their use, despite the presence of cryofibrinogen. In the other case, 'agglutination' was reversed by warming the bag, and plasma was removed before freezing.

The use of a national transplant registry to benchmark transplant outcome for patients undergoing autologous and allogeneic stem cell transplantation in the United Kingdom and Ireland

As part of its clinical governance programme the British Society for Blood and Marrow Transplantation (BSBMT) undertook an analysis of transplant outcome for adults undergoing human leucocyte antigen - identical sibling allogeneic transplantation for chronic myeloid leukaemia (CML) in first chronic phase (CP1) or autologous transplantation for Hodgkin's disease (HD). The study aimed to compare transplant-related mortality (TRM) and survival for patients reported to the BSBMT with patients transplanted in the rest of Europe, reported to the European Group for Blood and Marrow Transplantation (EBMT). The outcomes for 104 allogeneic transplants for CML in 24 UK/Irish centres were compared with 775 allografts in 145 other European centres. For HD, 241 autografts from 38 UK/Irish centres were compared with 1145 transplants in 239 other European centres. For both diseases, the cohorts were broadly matched with the exception of CML, where 85% of patients were transplanted <1 year from diagnosis in the UK/Ireland compared with 68% in the EBMT (P = 0.001). Cox regression analysis was undertaken using known delineated variables affecting transplant outcome in addition to the registry of origin. The adjusted survival curves for CML showed no significant differences between the two groups, with 3-year survival probabilities of 70.2% and 67.1% for the EBMT and BSBMT cohorts respectively. Likewise, the analysis for HD showed overlapping survival curves, with 3-year survival probabilities of 71.8% (EBMT) and 70.8% (BSBMT). TRM was not statistically different in either disease. This study demonstrates the potential for using national registries to benchmark transplant outcome against the EBMT registry.