Search

Summary: This prospective multicentre trial evaluated the safety and the efficacy of a thiotepa/melphalan‐based reduced intensity conditioning (RIC) haematopoietic stem cell transplantation (HSCT) in children and adolescents with chronic myeloid leukaemia (CML) in chronic phase (CP). Thirty‐two patients were transplanted from matched siblings or matched unrelated donors. In 22 patients, HSCT was performed due to insufficient molecular response or loss of response to first‐ or second‐generation tyrosine kinase inhibitor (TKI), with pretransplant BCR::ABL1 transcripts ranging between 0.001% and 33%. The protocol included a BCR::ABL1‐guided intervention with TKI retreatment in the first year and donor lymphocyte infusions (DLI) in the second‐year post‐transplant. All patients engrafted. The 1‐year transplant‐related mortality was 3% (confidence interval [CI]: 0%–6%). After a median follow‐up of 6.3 years, 5‐year overall survival and event‐free survival are 97% (CI: 93%–100%) and 91% (CI: 79%–100%) respectively. The current 5‐year leukaemia‐free survival with BCR::ABL1 <0.01% is 97% (CI: 88%–100%) and the current TKI‐ and DLI‐free survival is 95% (CI: 85%–100%). The incidence of chronic graft‐versus‐host disease (GvHD) was 32%, being severe in four patients (13%). At last follow‐up, 31 patients are GvHD‐free and have stopped immunosuppression. RIC HSCT following pretreatment with TKI is feasible and effective in children and adolescents with CP‐CML with an excellent disease‐free and TKI‐free survival. [ABSTRACT FROM AUTHOR]

Children with B cell malignancies refractory to standard therapy are known to have a poor prognosis and very limited treatment options. Here, we report on the treatment and follow-up of ten patients diagnosed with relapsed or refractory mature B-cell Non Hodgkin Lymphoma (B- NHL), Burkitt leukaemia (B- AL) or pre B-acute lymphoblastic leukaemia (pre B- ALL). All children were treated with FBTA05 (now designated Lymphomun), an anti- CD3 x anti- CD20 trifunctional bispecific antibody (trAb) in compassionate use. Within individual treatment schedules, Lymphomun was applied (a) after allogeneic stem cell transplantation (allo- SCT, n = 6) to induce sustained long-term remission, or (b) stand alone prior to subsequent chemotherapy to eradicate residual disease before allo- SCT ( n = 4). Nine of ten children displayed a clinical response: three stable diseases ( SD), one partial remission ( PR) and five induced or sustained complete remissions ( CR). Five of these nine responders died during follow-up. The other patients still maintain CR with a current overall survival of 874-1424 days (median: 1150 days). In conclusion, despite the dismal clinical prognosis of children refractory to standard therapy, immunotherapy with Lymphomun resulted in a favourable clinical outcome in this cohort of refractory paediatric patients. [ABSTRACT FROM AUTHOR]

Human mesenchymal stromal cells (MSC) possess immunosuppressive and antimicrobial effects that are partly mediated by the tryptophan-catabolizing enzyme indoleamine-2,3-dioxygenase (IDO). Therefore MSC represent a promising novel cellular immunosuppressant which has the potential to control steroid-refractory acute graft versus host disease (GvHD). In addition,MSC are capable of reducing the risk of infection in patients after haematopoietic stem cell transplantation (HST). Recent data indicate that signals fromthe microenvironment including those frommicrobesmay modulate MSC effector functions. As Cytomegalovirus (CMV) represents a prominent pathogen in immunocompromised hosts, especially in patients following HST, we investigated the impact of CMV infection on MSC-mediated effects on the immune system. We demonstrate that CMV-infected MSC lose their cytokine-induced immunosuppressive capacity and are no longer able to restrictmicrobial growth. IDO expression is substantially impaired following CMV infection of MSC and this interaction critically depends on intact virus and the number of MSC as well as the viral load. Since overt CMV infection may undermine the clinical efficacy of MSC in the treatment of GvHD in transplant patients, we recommend that patients scheduled forMSC therapy should undergo thorough evaluation for an active CMV infection and receive CMV-directed antiviral therapy prior to the administration of MSC. [ABSTRACT FROM AUTHOR]

The treatment outcome of children with refractory acute leukaemia or relapse post-stem cell transplantation is dismal. We report 10 children (non-remission n = 7) who underwent a new haploidentical transplant approach utilizing unmanipulated bone marrow followed by CD6-depleted peripheral blood stem cells. Nine patients had successful engraftment and no evidence of leukaemia. Acute and chronic graft-versus-host-disease was observed in five and three patients, respectively; two patients died of treatment-related toxicity. Seven patients relapsed after 7 (range 3-34) months, however two patients are alive at 6·5 and 7·0 years. This approach provides anti-leukaemic activity even in heavily pre-treated children but long-term disease control requires further intervention. [ABSTRACT FROM AUTHOR]

Although the substantial risk for invasive pneumococcal disease is well recognized in children after allogeneic stem cell transplantation, little is known about the specific immunity against pneumococci in children after cytotoxic therapy for acute lymphoblastic leukaemia (ALL). We therefore assessed the spontaneous reconstitution of humoral immunity against pneumococcal antigens, of total IgG and the IgG2 subclass, and of lymphocyte subsets in a total of 53 children treated for ALL. None of the patients had received pneumococcal vaccination prior to or after therapy for ALL. At 3 and 9 months after completion of chemotherapy, most patients had levels of specific antibodies to pneumococcal antigens below the presumed threshold of protection and significantly lower than those of age-matched unvaccinated healthy controls. In contrast, at 9 months after completion of therapy, only a minority of patients had immunoglobulin concentrations or lymphocyte subset counts below the age-matched reference value. Our data indicate that patients with ALL who are unvaccinated against pneumococci have a selective immunodeficiency with an impaired antibody protection against pneumococci for up to 9 months after completion of therapy. Therefore, effective prevention, including chemoprophylaxis and active immunization, has to be considered in this patient population. [ABSTRACT FROM AUTHOR]

Nerve growth factor (NGF) plays a pivotal role in cellular survival/death decisions with the low affinity receptor p75NTR predominately transmitting anti-proliferative signals. In spite of its established role in B-cell function and identification as a prognostically favourable marker in a number of malignancies, little is known about the expression pattern and prognostic significance of p75NTR in B cell precursor-acute lymphoblastic leukaemia (BCP-ALL). p75NTR expression was prospectively studied on primary ALL-blasts in a cohort of paediatric patients with common ALL ( n = 86) and preB-ALL ( n = 34) treated within the Co-operative study group for childhood acute lymphoblastic leukaemia (CoALL) protocol, CoALL06-97. Flow cytometric analysis showed that almost half of the patients expressed no or negligible amounts of p75NTR (<10%). The median expression in patients expressing p75NTR beyond that threshold was 49% (range 11–100%). In patients classified as low-risk at diagnosis, p75NTR expression was significantly higher than in high-risk patients ( P = 0·001). Of note, p75NTR expression was lower in the 21 patients who subsequently developed relapse compared with those remaining in remission ( P = 0·038). Accordingly, relapse-free survival was significantly better in patients expressing high surface p75NTR ( P = 0·041). Thus, in this prospective analysis, high p75NTR expression was a strong prognostic marker that identified a group of paediatric ALL patients with favourable outcome. [ABSTRACT FROM AUTHOR]

Asplenia and other conditions of immunodeficiency are established risk factors for invasive pneumococcal disease (IPD). There are no current data available on the risk of IPD in children with acute lymphoblatic leukaemia (ALL), the most common type of childhood malignancy. This study combined data from a nation-wide surveillance for IPD and the German childhood cancer registry, and showed that children with ALL carry a more than 10-fold higher risk for IPD than the general paediatric population. As a substantial proportion of IPD occurs during maintenance chemotherapy, children with ALL may represent candidates for the evaluation of prophylactic interventions including vaccination. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses various papers within the issue on topics including biological aspects and clinical applications of multipotent mesenchymal stromal cells.

Osteonecrosis (ON) was prospectively assessed in 557 children and adolescents in the Berlin-Frankfurt-Münster Stem Cell Transplantation in children with acute lymphoblastic leukaemia 2003 trial. Median age at haematopoietic stem cell transplantation (HSCT) was 10·3 years (range 0·5-26). Cumulative incidence of symptomatic ON (sON) was 9% at 5 years (standard deviation 1%), median time from HSCT to diagnosis of sON was 12·4 months (range 1-126). Multivariate analysis identified age at HSCT [10-15 years vs. <10 years: hazard ratio (HR) 3·73, P = 0·009; >15 years vs. <10 years: HR 5·46, P = 0·001], diagnosis of sON prior to HSCT and chronic graft-versus-host disease (yes versus no: HR 2·696, P = 0·015) as significant independent risk factors for the development of sON., (© 2018 British Society for Haematology and John Wiley & Sons Ltd.)

Relapse remains the major cause of treatment failure in children with high-risk acute lymphoblastic leukaemia (ALL) undergoing allogeneic haematopoietic stem-cell transplantation (allo-SCT). Prognosis is considered dismal but data on risk factors and outcome are lacking from prospective studies. We analysed 242 children with recurrence of ALL after first allo-SCT enrolled in the Berlin-Frankfurt-Munster (BFM) ALL-SCT-BFM 2003 and ALL-SCT-BFM international 2007 studies. Median time from allo-SCT to relapse was 7·7 months; median follow-up from relapse after allo-SCT until last follow-up was 3·4 years. The 3-year event-free survival (EFS) was 15% and overall survival (OS) was 20%. The main cause of death was disease progression or relapse (86·5%). The majority of children (48%) received salvage therapy without second allo-SCT, 26% of the children underwent a second allo-SCT and 25% received palliative treatment only. In multivariate analyses, age, site of relapse, time to relapse and type of salvage therapy were identified as significant prognostic factors for OS and EFS, whereas factors associated with first SCT were not statistically significant. Combined approaches incorporating novel immunotherapeutic treatment options and second allo-SCT hold promise to improve outcome in children with post allo-SCT relapse., (© 2017 John Wiley & Sons Ltd.)

Nerve growth factor (NGF) plays a pivotal role in cellular survival/death decisions with the low affinity receptor p75NTR predominately transmitting anti-proliferative signals. In spite of its established role in B-cell function and identification as a prognostically favourable marker in a number of malignancies, little is known about the expression pattern and prognostic significance of p75NTR in B cell precursor-acute lymphoblastic leukaemia (BCP-ALL). p75NTR expression was prospectively studied on primary ALL-blasts in a cohort of paediatric patients with common ALL (n = 86) and preB-ALL (n = 34) treated within the Co-operative study group for childhood acute lymphoblastic leukaemia (CoALL) protocol, CoALL06-97. Flow cytometric analysis showed that almost half of the patients expressed no or negligible amounts of p75NTR (<10%). The median expression in patients expressing p75NTR beyond that threshold was 49% (range 11-100%). In patients classified as low-risk at diagnosis, p75NTR expression was significantly higher than in high-risk patients (P = 0.001). Of note, p75NTR expression was lower in the 21 patients who subsequently developed relapse compared with those remaining in remission (P = 0.038). Accordingly, relapse-free survival was significantly better in patients expressing high surface p75NTR (P = 0.041). Thus, in this prospective analysis, high p75NTR expression was a strong prognostic marker that identified a group of paediatric ALL patients with favourable outcome.