TGFß and IL10 have an impact on risk group and prognosis in childhood ALL.

BACKGROUND: Cytokines and their genes have been described to have an influence on incidence and prognosis in malignant, infectious and autoimmune disease. We previously described the impact of cytokine production on prognosis in paediatric standard-risk acute lymphoblastic leukaemia (ALL). PROCEDURE: In this study, we investigated the influence of cytokine gene polymorphisms (TNFα, TGFß, IL10 and IFNγ) on frequency, risk group and prognosis in 95 paediatric ALL-patients. We further report on intracellular production of these cytokines in T-cells. RESULTS: IL10 high-producer-haplotypes were reduced in ALL-patients compared with healthy controls and resulted in a reduced relapse rate compared with low-producer haplotypes. TGFß high-producer-haplotypes were correlated with a high initial blast-count (codon 25: G/G) and were elevated in high-risk ALL-patients (codon 10: T/T). IL10 was positively and IFNγ-production was negatively correlated with initial blast-count. At diagnosis the expression of TNFα and IFNγ was reduced in patients compared with healthy controls. This was more pronounced in high-risk and in T-ALL-patients. CONCLUSION: We conclude that gene-polymorphisms of the regulatory/anti-inflammatory cytokines, TGFß and IL10, but not of the pro-inflammatory cytokines, IFNγ and TNFα, have an impact on prognosis and risk-group of ALL. However, the reduced capacity to produce pro-inflammatory cytokines at diagnosis may serve as another important, functional risk factor. These data may help in further risk stratification and adaptation of therapy-intensity in paediatric patients with ALL.

Successful treatment of an infant with CDA type II by intrauterine transfusions and postnatal stem cell transplantation.

Congenital dyserythropoietic anemias are rare hematological disorders leading to ineffective erythropoiesis with chronic anemia, complicated by iron overload. Here we present a remarkable clinical course of an infant with CDA type II who first presented as a severe fetal hydrops, requiring serial intrauterine red cell transfusions. While postnatal transfusion dependency persisted, the patient was successfully transplanted with a myeloablative conditioning regimen and peripheral blood stem cells of a matched donor. We believe that allogeneic HSCT is a reasonable therapeutic approach for patients with very severe CDA, even if only a matched unrelated donor is available.

Indication for allogeneic stem cell transplantation in Glanzmann's thrombasthenia.

Glanzmann's thrombasthenia (GT) is an autosomal recessive disorder characterized by a lack of thrombocyte aggregation due to the absence of thrombocyte glycoproteins IIb and αIIbß3. The role of haematopoietic stem cell transplantation (HSCT) in GT remains controversial. However, HSCT offers the only curative approach for patients with a severe clinical phenotype. In this review, we will discuss the limitation of current status evidence and the specific risk of GT, in particular the alloimmunization and refractoriness to thrombocyte infusions. 19 successful HSCT in 18 GT type I patients have been reported. Mean age at transplantation was 5 years. All patients are still alive. The majority received sibling bone marrow transplant with busulfan and cyclophosphamid conditioning. GvHD incidence was within the normal range, but 10 patients showed alloimmunization of thrombocytes. Median follow up is 25 months.

Allo-SCT using BU, CY and melphalan for children with AML in second CR.

Based on the results from the AML-BFM 98 trial, hematopoietic SCT (HSCT) is recommended for children with AML in second CR only. Here, we retrospectively analyze interphase data of children who underwent HSCT after myeloablative conditioning with BU, CY, and melphalan (BuCyMel) for AML in second remission (CR2) between 1998 and 2009. Out of 152 children, transplant data were available on 109 individuals. Sixty out of 109 children (55%) received BuCyMel. Median age at HSCT was 12.2 years (range 3.0; 18.3). GVHD prophylaxis mostly consisted of CsA and short term MTX with or without antithymocyte globulin. Matched-sibling donors were used for 6/60 analyzed recipients, the remainder either received grafts from matched unrelated (30/60) or mismatched donors. OS after 5 years was 62% (s.e. 6%), relapse incidence 35% (18/60 children) and treatment-related mortality accounted for 12% (7/60) of fatal events. In conclusion, even taking into account possible selection bias in this retrospective analysis, HSCT in CR2 using BuCyMel resulted in a respectable OS. Based on this data the prospective, controlled and centrally monitored AML SCT-BFM 2007 trial has started to recruit patients in January 2010 aiming to generate valid outcome data for further strategy decisions.

Long-term follow-up of children conditioned with Treosulfan: German and Austrian experience.

We report the long-term follow-up of children transplanted with Treosulfan (TREO)-based conditioning in Germany and Austria. Nine centres reported a total of 109 transplantations. Patients were stratified according to the paediatric TRM risk score derived from the paediatric BMT registry (PRST) and compared with the historical transplant population of this registry. Underlying diseases were malignancies, immunodeficiencies, and haematologic and metabolic disorders. TREO total dose ranged from 21-42 g/m(2). Additional conditioning drugs included fludarabine, thiotepa, melphalan, CY and/or TBI. EFS at 3 years for non-malignant and malignant diseases was 88% and 49%, respectively. Leukaemia patients in remission had a survival of 51% at 3 years; nonremission patients relapsed and died within 18 months. TRM and OS in the low-risk groups 0 and 1 were similar to PRST controls. TRM in the high-risk groups 2 and 3 was markedly lower (9% vs 28% and 13% vs 53%, respectively) than in the PRST group, but OS was similar. In conclusion, TREO-based conditioning regimens in children resulted in excellent engraftment and long-term survival in nonmalignant disease. In high-risk malignancy, low acute toxicity was followed by low TRM but it did not translate into increased survival.

Human leukocyte antigen distribution in German Caucasians with advanced Ewing's sarcoma.

BACKGROUND: Risk stratification criteria for patients with Ewing's sarcoma family of tumors (ESFT) are still limited. We hypothesized divergent human leukocyte antigen (HLA) patterns in ESFT patients and compared HLA-A, -B and -DR phenotype frequencies of patients with advanced ESFT with those of healthy controls. PATIENTS: HLA types of all German Caucasian patients with advanced ESFT and available HLA-A, -B and -DR data registered in the European Group for Blood and Marrow Transplantation, Paediatric Registry for Stem Cell Transplantation and the MetaEICESS data bases (study group, n=30) were retrospectively compared with HLA types of healthy German stem cell donors (control group, n=8 862 for single HLA frequencies and n=8 839 for allele combinations). Study group patients had been immuno-typed due to eligibility for allogeneic stem cell transplantation for high risk of treatment failure, and thus constituted a selected subgroup of ESFT patients. RESULTS: After Bonferroni correction for multiple testing (PC), phenotype frequencies of HLA-A24 remained significantly higher in the study group compared to controls (PC<0.05). Furthermore, several HLA combinations were significantly more frequent in the study group compared to controls (all PC<0.05). CONCLUSION: We report an increased incidence of circumscribed HLA patterns in German Caucasians with advanced ESFT. The possible clinical significance of this observation has to be re-assessed in prospective trials comprising larger ESFT patient numbers of all risk groups.

Allogeneic hematopoietic stem cell transplantation in Glanzmann thrombasthenia complicated by platelet alloimmunization.

BACKGROUND: For Thrombasthenia Glanzmann (GT) patients presenting with a severe clinical phenotype due to complete lack of thrombocyte function or increased titres of anti-platelet antibodies hematopoietic stem cell transplantation (SCT) is the only curative therapy. CASE REPORT: We report the case of a 13-month-old boy, presenting with a severe course of GT, who was successfully treated with an HLA-identical sibling bone marrow transplant. SCT was complicated by anti-platelet alloimmunization after platelet transfusion successfully treated with high dosage immunoglobulins (2 g/kg) and partial plasma exchange. CONCLUSION: SCT may be a viable option for selected patients with GT. However, SCT in GT carries its own significant risks, resulting from the development of anti-platelet antibodies. A critical risk-benefit analysis is mandatory prior to SCT.

No improvement of survival with reduced- versus high-intensity conditioning for allogeneic stem cell transplants in Ewing tumor patients.

BACKGROUND: Outcomes of Ewing tumor (ET) patients treated with allogeneic stem cell transplantation (allo-SCT) were compared regarding the use of reduced-intensity conditioning (RIC) and high-intensity conditioning (HIC) regimens as well as human leukocyte antigen (HLA)-matched and HLA-mismatched grafts. PATIENTS AND METHODS: We retrospectively analyzed data of 87 ET patients from the European Group for Blood and Marrow Transplantation, Pediatric Registry for Stem Cell Transplantations, Asia Pacific Blood and Marrow Transplantation and MetaEICESS registries treated with allo-SCT. Fifty patients received RIC (group A) and 37 patients received HIC (group B). Twenty-four patients received HLA-mismatched grafts and 63 received HLA-matched grafts. RESULTS: Median overall survival was 7.9 months [±1.24, 95% confidence interval (CI) 5.44-10.31] for group A and 4.4 months (±1.06, 95% CI 2.29-6.43) for group B patients (P = 1.3). Death of complications (DOC) occurred in 4 of 50 (0.08) and death of disease (DOD) in 33 of 50 (0.66) group A and in 16 of 37 (0.43) and 17 of 37 (0.46) group B patients, respectively. DOC incidence was decreased (P < 0.01) and DOD/relapse increased (P < 0.01) in group A compared with group B. HLA mismatch was not generally associated with graft-versus-Ewing tumor effect (GvETE). CONCLUSIONS: There was no improvement of survival with RIC compared with HIC due to increased DOD/relapse incidence after RIC despite less DOC incidence. This implicates general absence of a clinically relevant GvETE with current protocols.

Stem cells, melanoma and cancer stem cells: the good, the bad and the evil?

Most cancers contain morphologically heterogeneous populations of cells. While this observation may partly be explained by the coexistence of multiple genetic sub-clones arising through independent somatic mutations and/or as a result of differentiation processes in the tumor microenvironment, it also implies that the tumor may be formed from undifferentiated ''stem cell-like'' cells called ''cancer stem cells'' or ''cancer-initiating cells''. These cells are thought to constitute one or several rare subpopulations in a given tumor and would be strongly responsible for initiation of tumor development and growth as well as for metastasis and recurrence after cytoreductive therapy. However, while the concept of cancer stem cells has been first established for human myeloid leukemia in the 1960s, it has only much later been extended to other solid tumors such as breast or brain cancers and most recently to melanoma. Thus, it is presently unclear which role a sufficiently characterized population of melanoma stem cells plays in cancer promotion and progression. Here, we review the emerging melanoma stem cell model and discuss the biological and therapeutic implications of the model.

Transplantation of highly purified peripheral-blood CD34+ progenitor cells from related and unrelated donors in children with nonmalignant diseases.

Transplantation of allogeneic stem cells is currently the only curative treatment for some nonmalignant pediatric diseases. We investigated whether transplantation of purified CD34(+) stem cells prevents acute and chronic GvHD and reduces transplant-related mortality. A total of 25 pediatric patients with nonmalignant diseases underwent allogeneic transplantation from 26 donors (matched related n=4, matched or partially matched unrelated n=14, mismatched related n=8). All grafts were purified peripheral-blood CD34(+) stem cells mobilized with G-CSF. Patients received a median of 12.9 x 10(6) CD34(+) progenitor cells with a median of 6.1 x 10(3) contaminating T-lymphocytes per kilogram of body weight. No post transplant immunosuppressive drugs were given for prophylaxis of GvHD. Engraftment was seen in 21 patients. Three patients engrafted after a second transplant and one patient failed to engraft. Two patients had autologous reconstitution 1.5 years post transplant and one of them was successfully retransplanted. No acute GvHD >grade II was seen, and only two patients developed limited, chronic GvHD. In all, 22 patients (88%) are alive with a median follow-up of 3.7 years. In total, 19 patients (76%) are free of disease or of progression. Transplantation of highly purified peripheral-blood CD34(+) stem cells is associated with low toxicity in patients with nonmalignant diseases.

A prospective comparison of immune reconstitution in pediatric recipients of positively selected CD34+ peripheral blood stem cells from unrelated donors vs recipients of unmanipulated bone marrow from related donors.

Positively selected CD34(+) hematopoietic stem cells from unrelated donors (UD-HSCT) have been successfully transplanted, but little is known about immune reconstitution in this setting. Here we report a prospective comparison of immune reconstitution in recipients of UD-HSCT and of unmanipulated bone marrow from matched sibling donors (MSD-BMT). T-cell reconstitution occurred more than 100 days later in the UD-HSCT than in the MSD-BMT group. The first T cells after UD-HSCT were almost exclusively CD45RO(+) HLA-DR(+), whereas early-emerging T cells after MSD-BMT more frequently expressed CD62L, CD28, and CD25. In both groups, numbers of CD45RA(+) naive T cells increased after 180 days. After UD-HSCT, the T-cell-receptor (TCR)-repertoire was severely skewed and showed significantly reduced diversity during the first year, but only minor abnormalities were seen after MSD-BMT. TCR-diversity increased simultaneously with the number of naive T cells. In both groups, we observed transient expansions of gammadelta T cells. B cells were reconstituted more rapidly in UD-HSCT than in MSD-BMT recipients, whereas the rapidity of NK-cell reconstitution was similar in the two groups. In summary, T-cell reconstitution was slower after UD-HSCT than after MSD-BMT because of the delayed recovery of early memory-type T cells with reduced TCR-diversity, whereas naive T-, NK-, and B cells were reconstituted similarly in the two groups.

Cidofovir for adenovirus infections after allogeneic hematopoietic stem cell transplantation: a survey by the Infectious Diseases Working Party of the European Group for Blood and Marrow Transplantation.

Adenovirus is an important cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation and there is no established therapy. Cidofovir has in vitro efficacy against adenovirus. We performed a retrospective analysis of 45 patients treated with cidofovir for adenovirus from 10 centers. In total, 16 patients had definite adenovirus disease, 13 probable disease, and 16 asymptomatic infections. A total of 31 (69%) patients were successfully treated with cidofovir, 10 failed, and four were not evaluable owing to early death from other causes. Cidofovir therapy was successful in 10 patients with adenovirus disease, 10 patients with probable disease, and in 10 patients with asymptomatic infections. The overall survival at 28 days and 6 months after initiation of cidofovir therapy was 76 and 46%, respectively. Of the patients, 18 developed toxicity associated with cidofovir: 14 developed renal toxicity and four other types of toxicities. We conclude that cidofovir may be useful against adenovirus after allogeneic hematopoietic stem cell transplantation but additional studies are needed.

A prospective analysis of the pattern of immune reconstitution in a paediatric cohort following transplantation of positively selected human leucocyte antigen-disparate haematopoietic stem cells from parental donors.

Transplantation of haematopoietic stem cells from human leucocyte antigen (HLA)-disparate parental donors presents a promising new approach for the treatment of patients lacking a HLA-matched donor. Success against major obstacles such as graft-versus-host disease (GvHD) and graft rejection has recently been demonstrated, so that immune reconstitution is one of the prime factors that determines the long-term prognosis following transplantation. Twenty children transplanted with megadoses of highly purified CD34(+) haematopoietic stem cells after rigorous T-cell depletion were prospectively monitored for their immune reconstitution during the first post-transplant year. Natural killer (NK) cells showed a marked increase on d +30. T and B cells began to reconstitute on d +72 and +68 respectively. During extended follow-up, their numbers and proliferative capacity upon mitogen stimulation continually increased. Early reconstituting T cells were predominantly of a primed, activated phenotype with severely skewed T-cell receptor (TCR)-repertoire complexity. Naive T cells emerged 6 months post transplantation, paralleled by an increase in TCR-repertoire diversity. All patients self-maintained sufficient immunoglobulin levels after d +200. This study demonstrates that paediatric recipients of highly purified, haploidentical stem cells are able to reconstitute functioning T-, B- and NK-cell compartments within the first post-transplant year. This, together with the absence of significant GvHD, provides a strong indication for this approach to be considered in children who lack a HLA-matched donor.

OKT-3-based reconditioning regimen for early graft failure in HLA-non-identical stem cell transplants.

Primary non-engraftment or early rejection after transplantation of haematopoietic stem cells represent life-threatening complications of allogeneic stem cell transplantation. Management of early graft failure has been problematic, as the risk of fatal infectious complications increases with the time of pancytopenia and as a second transplant preceded by a conventional myeloablative conditioning regimen has been associated with high rates of cumulative organ toxicity. For paediatric patients with early graft failure following the transplantation of highly purified major histocompatibility complex (MHC)-disparate haematopoietic stem cells, we have evaluated an immunosuppressive OKT-3/methylprednisolone-based reconditioning regimen with low toxicity in preparation for a secondary transplant of purified haematopoietic stem cells from the same donor. This report presents the results from a 4-year pilot study including six patients with early graft failure. The results demonstrate that this antibody-based regimen can be used effectively to prepare patients for secondary transplantation. Successful engraftment after a second transplant procedure was achieved in five of these six high-risk patients. The median interval between first and second transplant was 27 d (range 22-51 d), and the median time for engraftment was 10 d (range 9-13 d). Chimaerism analysis of microsatellite regions by polymerase chain reaction (PCR) demonstrated complete donor chimaerism in four of these patients within the first month after secondary transplant and revealed mixed chimaerism in one patient who converted to complete chimaerism after T-cell add-back.