Dental status does not predict infection during stem cell transplantation: a single-center survey

Minimal residual disease (MRD) at the end of induction therapy is important for risk stratification of acute lymphoblastic leukaemia (ALL), but bone marrow (BM) aspiration is often postponed or must be repeated to fulfil qualitative and quantitative criteria for morphological assessment of haematological remission and/or MRD analysis. The impact of BM aspiration delay on measured MRD levels and resulting risk stratification is currently unknown. We analysed paired MRD data of 289 paediatric ALL patients requiring a repeat BM aspiration. MRD levels differed in 108 patients (37%) with a decrease in the majority (85/108). This would have resulted in different risk group allocation in 64 of 289 patients (23%) when applying the ALL-Berlin-Frankfurt-Münster 2000 criteria. MRD change was associated with the duration of delay; 40% of patients with delay ≥7 days had a shift to lower MRD levels compared to only 18% after a shorter delay. Patients MRD-positive at the original but MRD-negative at the repeat BM aspiration (n = 50) had a worse 5-year event-free survival than those already negative at first aspiration (n = 115) (86 ± 5% vs. 94 ± 2%; P = 0·024). We conclude that BM aspirations should be pursued as scheduled in the protocol because delayed MRD sampling at end of induction may result in false-low MRD load and distort MRD-based risk assessment.

Allogeneic hematopoietic stem cell transplantation is required as rescue therapy in about 20% of pediatric patients with acute lymphoblastic leukemia. However, the relapse rates are considerable, and relapse confers a poor outcome. Early assessment of the risk of relapse is therefore of paramount importance for the development of appropriate measures. We used the EuroChimerism approach to investigate the potential impact of lineage-specific chimerism testing for relapse-risk analysis in 162 pediatric patients with acute lymphoblastic leukemia after allogeneic stem cell transplantation in a multicenter study based on standardized transplantation protocols. Within a median observation time of 4.5 years, relapses have occurred in 41/162 patients at a median of 0.6 years after transplantation (range, 0.13–5.7 years). Prospective screening at defined consecutive time points revealed that reappearance of recipient-derived cells within the CD34+ and CD8+ cell subsets display the most significant association with the occurrence of relapses with hazard ratios of 5.2 (P=0.003) and 2.8 (P=0.008), respectively. The appearance of recipient cells after a period of pure donor chimerism in the CD34+ and CD8+ leukocyte subsets revealed dynamics indicative of a significantly elevated risk of relapse or imminent disease recurrence. Assessment of chimerism within these lineages can therefore provide complementary information for further diagnostic and, potentially, therapeutic purposes aiming at the prevention of overt relapse. This study was registered at clinical.trials.gov with the number NC01423747.

In a prospective multicentre study of bloodstream infection (BSI) from November 01, 2007 to July 31, 2010, seven paediatric cancer centres (PCC) from Germany and one from Switzerland included 770 paediatric cancer patients (58 % males; median age 8.3 years, interquartile range (IQR) 3.8–14.8 years) comprising 153,193 individual days of surveillance (in- and outpatient days during intensive treatment). Broviac catheters were used in 63 % of all patients and Ports in 20 %. One hundred forty-two patients (18 %; 95 % CI 16 to 21 %) experienced at least one BSI (179 BSIs in total; bacteraemia 70 %, bacterial sepsis 27 %, candidaemia 2 %). In 57 %, the BSI occurred in inpatients, in 79 % after conventional chemotherapy. Only 56 % of the patients showed neutropenia at BSI onset. Eventually, patients with acute lymphoblastic leukaemia (ALL) or acute myeloblastic leukaemia (AML), relapsed malignancy and patients with a Broviac faced an increased risk of BSI in the multivariate analysis. Relapsed malignancy (16 %) was an independent risk factor for all BSI and for Gram-positive BSI.

PURPOSE:To elucidate the impact of minimal residual disease (MRD) after allogeneic transplantation, the Acute Lymphoblastic Leukemia Berlin-Frankfurt-Münster Stem Cell Transplantation Group (ALL-BFM-SCT) conducted a prospective clinical trial.PATIENTS AND METHODS:In the ALL-BFM-SCT 2003 trial, MRD was assessed in the bone marrow at days +30, +60, +90, +180, and +365 after transplantation in 113 patients with relapsed disease. Standardized quantification of MRD was performed according to the guidelines of the Euro-MRD Group.RESULTS:All patients showed a 3-year probability of event-free survival (pEFS) of 55%. The cumulative incidence rates of relapse and treatment-related mortality were 32% and 12%, respectively. The pEFS was 60% for patients who received their transplantations in second complete remission, 50% for patients in ≥ third complete remission, and 0% for patients not in remission (P = .015). At all time points, the level of MRD was inversely correlated with event-free survival (EFS; P < .004) and positively correlated with the cumulative incidence of relapse (P < .01). A multivariable Cox model was fitted for each time point, which showed that MRD ≥ 10(-4) leukemic cells was consistently correlated with inferior EFS (P < .003). The accuracy of MRD measurements in predicting relapse was investigated with time-dependent receiver operating curves at days +30, +60, +90, and +180. From day +60 onward, the discriminatory power of MRD detection to predict the probability of relapse after 1, 3, 6, and 9 months was more than 96%, more than 87%, more than 71%, and more than 61%, respectively.CONCLUSION:MRD after transplantation was a reliable marker for predicting impending relapses and could thus serve as the basis for pre-emptive therapy.

PURPOSEAlthough hematopoietic stem-cell transplantation is widely performed in children with high-risk acute lymphoblastic leukemia (ALL), the influence of donor types is poorly understood. Thus, transplantation outcomes were compared in the prospective multinational Berlin-Frankfurt-Muenster (BFM) study group trial: ALL-SCT-BFM 2003 (Allogeneic Stem Cell Transplantation in Children and Adolescents with Acute Lymphoblastic Leukemia).PATIENTS AND METHODSAfter conditioning with total-body irradiation and etoposide, 411 children with high-risk ALL received highly standardized stem-cell transplantations during the first or later remissions. Depending on donor availability, grafts originated from HLA-genoidentical siblings or from HLA-matched unrelated donors who were identified and matched by high-resolution allelic typing and were compatible in at least 9 of 10 HLA loci.RESULTSFour-year event-free survival (± standard deviation [SD]) did not differ between patients with transplantations from unrelated or sibling donors (0.67 ± 0.03 v 0.71 ± 0.05; P = .405), with cumulative incidences of nonrelapse mortality (± SD) of 0.10 ± 0.02 and 0.03 ± 0.02 (P = .017) and relapse rates (± SD) of 0.22 ± 0.02 and 0.24 ± 0.04 (P = .732), respectively. Among recipients of transplantations from unrelated donors, no significant differences in event-free survival, overall survival, or nonrelapse mortality were observed between 9/10 and 10/10 matched grafts or between peripheral blood stem cells and bone marrow. The absence of chronic graft-versus-host disease had no effect on event-free survival. Engraftment was faster after bone marrow transplantation from siblings and was associated with fewer severe infections and pulmonary complications.CONCLUSIONOutcome among high-risk pediatric patients with ALL after hematopoietic stem-cell transplantation was not affected by donor type. Standardized myeloablative conditioning produced a low incidence of treatment-related mortality and effective control of leukemia.

We report on an 8 year old boy with primary cardiac anaplastic large cell lymphoma (ALCL), in whom the diagnosis was challenging and who was treated with modified chemotherapy without radiation therapy according to the ALCL 99 study protocol [1]. Two years and 4 months after completion of therapy the boy is in complete remission with normal cardiac function.

Allogeneic hematopoietic stem cell transplantation (HSCT) from unrelated donors became a common practice during the last years to rescue children and adolescents with high risk acute lymphoblastic leukaemia (ALL) who lack an HLA identical sibling donor (MSD). However, heterogeneous approaches in donor selection and transplantation methods hamper the interpretation of available data. Therefore we compared the influence of donor source under standardized methods. Twenty-nine centres participated in the prospective trial to evaluate whether the results of HSCT from HLA matched donors (MD) are comparable to those of HLA identical siblings in patients with high risk ALL. 118 patients (age 0.5-18 years, med. 10.2) underwent MSD-HSCT and 313 MD-HSCT. 218 pts were in first and 213 beyond 1st remission. Unrelated donors were compatible for at least 9/10 matches with allelic typing. GvHD-prophylaxis consisted of CSA only after MSD-HSCT and of CSA/MTX/ATG after MD-HSCT. Patients older than 2 years received total body irradiation and etoposide as conditioning regimen. The stem cell source was for 82% of the MSD-group bone marrow (BM), 10% received peripheral blood stem cells (PBSC) and some received cord blood (CB). In the MD-cohort, 66% received BM, 28% PBSC and the remaining CB or combinations. After a median follow up of 4.2 years, the 4-year disease free survival (DFS) is 0.70±0.04, the overall survival (OS) 0.77±0.04 after MSD-HSCT and after MD-HSCT DFS is 0.66±0.03, OS 0.73±0.03 (n.s.); 4-years relapse-incidence is 0.22±0.04 after MSD-HSCT and 0.23±0.02 after MD-HSCT (n.s.). Non-relapse mortality at 4 years is 0.06±0.02 for MSD and 0.10±0.02 for MD (p-value 0.228). In multivariate analysis the only significant impact on OS and DFS was 1st remission compared to 2nd or 3rd remission with a Hazard ratio of 1.71. However, engraftment was significantly better after MSD-HSCT: the median day to reach ANC >1000/μl/lymphocytes >100/μl/platelets >50.000/μl was 17/14/22 after MSD-HSCT and 22/23/32 after MD-HSCT (p < 0.001). This resulted in significant less severe infections ( ≥ grade 3 CTA 3.0) –18% vs. 40% (p < 0.01) and less severe pulmonary complications: 10% vs. 19% (p = 0.034). We conclude that despite excellent outcome with low GVHD-incidence and low NRM after HSCT from MD in children with high risk ALL the HSCT von MSD results in faster engraftment and immunoreconstitution and less severe infections and justifies the use of minor sibling donors.

SummaryTransplantation of T‐ and B‐cell depleted allografts from haploidentical family donors was evaluated within a prospective phase II trial in children with acute lymphoblastic leukaemia, acute myeloid leukaemia and advanced myelodysplastic syndrome (n = 46). 20 patients had active disease; 19 patients received a second or third stem cell transplantation (SCT). Toxicity‐reduced conditioning regimens consisted of fludarabine or clofarabine (in active disease only), thiotepa, melphalan and serotherapy. Graft manipulation was carried out with immunomagnetic microbeads. Primary engraftment occurred in 88%, with a median time to reach >1·0 × 109/l leucocytes, >20 × 109/l platelets and >0·1 × 109/l T‐cells of 10, 11 and 50 days, respectively. After retransplantation, engraftment occurred in 100%. Acute graft‐versus‐host disease (GvHD) grade II and III‐IV occurred in 20% and 7%, chronic GvHD occurred in 21%. Both conditioning regimens had comparable toxicity. Transplant‐related mortality (TRM) was 8% at one year and 20% at 5 years. Event‐free survival at 3 years was: 25% (whole group), 46% (first, second or third complete remission [CR], first SCT) vs. 8% (active disease, first SCT) and 20% (second or third SCT, any disease status). This approach allows first or subsequent haploidentical SCTs to be performed with low TRM. Patients in CR may benefit from SCT, whereas the results in patients with active disease were poor.

In pediatric acute lymphoblastic leukemia (ALL), the most important prognostic factor for the risk of relapse is the evaluation of minimal residual disease (MRD) at defined timepoints. The results of MRD analyses are not available at diagnosis to guide selection of the optimal treatment intensity already early on.

doi:10.1182/blood-2011-03-338707Prepublished online June 30, 2011;2011 118: 2077-2084€€€€van Dongen, Helmut Gadner, Andrea Biondi and Valentino ConterCazzaniga, Rolf Koehler, Franco Locatelli, Beat W. Schafer, Maurizio Arico, Karl Welte, Jacques J.M.Buldini, Alfred Reiter, Giuseppe Basso, Thomas Klingebiel, Chiara Messina, Richard Ratei, Giovanni Panzer-Grumayer, Anja Moricke, Rosanna Parasole, Martin Zimmermann, Michael Dworzak, BarbaraMartin Schrappe, Maria Grazia Valsecchi, Claus R. Bartram, Andre Schrauder, Renate€

Although immortalized cell lines have been extensively used to optimize treatment strategies in cancer, the usefulness of such in vitro systems to recapitulate primary disease is limited. Therefore, the design of in vivo models ideally utilizing patient‐derived material is of critical importance. In this regard, NOD.Cg‐PrkdcscidIL2rgtmWjl/Sz (NSG) mice have been reported to provide superior engraftment rates. However, limited data exist on the validity of such a model to constitute a surrogate marker for clinical parameters. We studied primary and serial engraftment on more than 200 NSG mice with 54 primary pediatric B cell precursor acute lymphatic leukemia (B‐ALL), myeloid leukemia (AML) and T cell leukemia (T‐ALL) samples, characterized the leukemogenic profile and correlated engraftment kinetics with clinical outcome. Median time to engraftment was 7–10 weeks and 90% of the mice engrafted. Male recipients conferred significantly higher engraftment levels than female recipients (p ≤ 0.004). PCR‐based minimal residual disease marker expression and fluorescence in situ hybridization confirmed the presence of patient‐specific genetic aberrations in mice. Transcriptome cluster analysis of genes known to be important in the leukemogenesis of all three diseases revealed that well‐known tumor‐regulating genes were expressed to a comparable extent in mice and men. The extent of engraftment and overall survival of NSG mice highly correlated with the individual prognosis of B‐ALL, AML and T‐ALL patients. Thus, we propose an in vivo model that provides a valuable preclinical tool to explore the heterogeneity of leukemic disease and exploit patient‐tailored leukemia‐targeting strategies within multivariate analyses.

Abstract Purpose Monitoring of minimal residual disease (MRD) after allogeneic stem cell transplantation (allo-SCT) by quantitative real-time PCR (qRT-PCR) of rearranged Ig- and TCR-genes may highlight patients with highest risk for relapse to whom pre-emptive treatment may be offered. Patients and Methods In the prospective phase 3 trial ALL-SCT-BFM-2003 (recruitment period 09/2003 to 09/2011; time point of analysis May 2013), MRD was assessed in bone marrow immediately on days +30, +60, +100, +200 and +365 post transplantation in 115 patients. Of these, 48 were male and 67 were female patients. All received a myeloablative conditioning regimen with TBI and VP 16. Patients received their transplant in CR2 (n=94), CR3 (n=21), CR4 (n=1) or NR (n=2). The transplantations were performed with bone marrow from matched sibling donors (MSD, n=23), matched unrelated donors (MUD, n=71) or with T-cell depleted stem cells from mismatched donors (MMD, n=21). Fifty-four patients were younger than 10 and 61 patients were older than 10 years at the time of transplant. Standardized quantification of MRD was performed according to the guidelines of the Euro-MRD-Group and MRD results were not released to the clinicians. Results The total group of patients showed a pEFS of 0.52±0.10; cumulative incidence of relapse (CIR) and cumulative incidence of treatment related mortality (CI TRM) was 0.41±0.11 and 0.19±0.09, respectively. In 76 patients, MRD could also be assessed prior to transplant: patients who were MRD negative (n=41) had a three year pEFS of 0.62±0.04, patients with a MRD load of <10E-3 (n=28) of 0.49±0.14 and none of the patients who were MRD positive >1E-3 survived their disease. MRD values post transplant were analyzed as time-dependent covariates. When analyzed either for the different time points or for the highest MRD value post transplant, MRD results had always significant influence on survival. Taken the highest MRD value post transplant, probabilities of pEFS and CIR were 0.65±0.11 and 0.23±0.09 for MRD negative patients (n=72), 0.36±0.18 resp. 0.75 ±0.18 for patients with MRD <10-3 (n=36) compared to 0.00±0.0 and 1.0±0.0 in patients who developed MRD ≥10-3 leukemic cells (n=07) (pEFS, P<0.0001; CIR, P<0.0001). In multivariate cox regression analysis, MRD prior and post transplantation, as well as indication for SCT, significantly influenced the probability of survival. It is noteworthy, that all patients who developed a MRD load of >10E-3 at any time after transplant finally developed relapse and died. However, 49% of patients who became MRD positive <10E-3 did not necessarily develop frank relapse. Here, dynamic evolution needs to be considered as 9/15 patients with an MRD load of <10E-3 at day 200 survived. However, if MRD was not cleared by day 365 all patients finally relapsed. Conclusion Assessment of MRD post transplant allows the identification of patients with impending relapse. All patients who developed MRD >10E-3 at any time post transplant finally relapsed. Therefore, MRD may serve as an endpoint for further pre-emptive therapies. Acknowledgment This trial was supported by the “Deutsche Knochenmarkspender Datei” (DKMS). Disclosures: No relevant conflicts of interest to declare.

Acute lymphoblastic leukemia (ALL) accounts for ∼25% of pediatric malignancies. Of interest, the incidence of ALL is observed ∼20% higher in males relative to females. The mechanism behind the phenomenon of sex-specific differences is presently not understood. Employing genome-wide genetic aberration screening in 19 ALL samples, one of the most recurrent lesions identified was monoallelic deletion of the 5' region of SLX4IP. We characterized this deletion by conventional molecular genetic techniques and analyzed its interrelationships with biological and clinical characteristics using specimens and data from 993 pediatric patients enrolled into trial AIEOP-BFM ALL 2000. Deletion of SLX4IP was detected in ∼30% of patients. Breakpoints within SLX4IP were defined to recurrent positions and revealed junctions with typical characteristics of illegitimate V(D)J-mediated recombination. In initial and validation analyses, SLX4IP deletions were significantly associated with male gender and ETV6/RUNX1-rearranged ALL (both overall P < 0.0001). For mechanistic validation, a second recurrent deletion affecting TAL1 and caused by the same molecular mechanism was analyzed in 1149 T-cell ALL patients. Validating a differential role by sex of illegitimate V(D)J-mediated recombination at the TAL1 locus, 128 out of 1149 T-cell ALL samples bore a deletion and males were significantly more often affected (P = 0.002). The repeatedly detected association of SLX4IP deletion with male sex and the extension of the sex bias to deletion of the TAL1 locus suggest that differential illegitimate V(D)J-mediated recombination events at specific loci may contribute to the consistent observation of higher incidence rates of childhood ALL in boys compared with girls.

PURPOSE:In children with intermediate risk of relapse of acute lymphoblastic leukemia (ALL), it is essential to identify patients in need of treatment intensification. We hypothesized that the prognosis of patients with unsatisfactory reduction of minimal residual disease (MRD) can be improved by allogeneic hematopoietic stem-cell transplantation (HSCT).PATIENTS AND METHODS:In the Acute Lymphoblastic Leukemia-Relapse Study of the Berlin-Frankfurt-Münster Group (ALL-REZ BFM) 2002, patients with an MRD level of ≥ 10(-3) (n = 99) at the end of induction therapy were allocated to HSCT, whereas those with an MRD level less than 10(-3) (n = 109) continued to receive chemotherapy. MRD was quantified by real-time polymerase chain reaction for clone-specific T-cell receptor/immunoglobulin gene rearrangements.RESULTS:The probability of event-free survival for patients with MRD ≥ 10(-3) was 64% ± 5% in ALL-REZ BFM 2002 compared with 18% ± 7% in the predecessor study ALL-REZ BFM P95/96 (P < .001). This was mainly achieved by reducing the cumulative incidence of subsequent relapse (CIR) at 8 years from 59% ± 9% to 27% ± 5% (P < .001). The favorable prognosis of patients with MRD less than 10(-3) could be confirmed in those with a late combined or isolated bone marrow B-cell precursor (BCP) -ALL relapse (CIR, 20% ± 5%), whereas patients with an early combined BCP-ALL relapse had an unfavorable outcome (CIR, 63% ± 13%; P < .001).CONCLUSION:Allogeneic HSCT markedly improved the prognosis of patients with intermediate risk of relapse of ALL and unsatisfactory MRD response. As a result, outcomes in this group approximated those of patients with favorable MRD response. Patients with early combined relapse require treatment intensification even in case of favorable MRD response, demonstrating the prognostic impact of time to relapse.

The Fc-engineered CD19 antibody MOR208 (XmAb5574) induces natural killer cell-mediated lysis of acute lymphoblastic leukemia cells from pediatric and adult patients