An Extensive Quality Control and Quality Assurance (QC/QA) Program Significantly Improves Inter-Laboratory Concordance Rates of Flow-Cytometric Minimal Residual Disease Assessment in Acute Lymphoblastic Leukemia: An I-BFM-FLOW-Network Report

Monitoring of minimal residual disease (MRD) by flow cytometry (FCM) is a powerful prognostic tool for predicting outcomes in acute lymphoblastic leukemia (ALL). To apply FCM-MRD in large, collaborative trials, dedicated laboratory staff must be educated to concordantly high levels of expertise and their performance quality should be continuously monitored. We sought to install a unique and comprehensive training and quality control (QC) program involving a large number of reference laboratories within the international Berlin-Frankfurt-Münster (I-BFM) consortium, in order to complement the standardization of the methodology with an educational component and persistent quality control measures. Our QC and quality assurance (QA) program is based on four major cornerstones: (i) a twinning maturation program, (ii) obligatory participation in external QA programs (spiked sample send around, United Kingdom National External Quality Assessment Service (UK NEQAS)), (iii) regular participation in list-mode-data (LMD) file ring trials (FCM data file send arounds), and (iv) surveys of independent data derived from trial results. We demonstrate that the training of laboratories using experienced twinning partners, along with continuous educational feedback significantly improves the performance of laboratories in detecting and quantifying MRD in pediatric ALL patients. Overall, our extensive education and quality control program improved inter-laboratory concordance rates of FCM-MRD assessments and ultimately led to a very high conformity of risk estimates in independent patient cohorts

Childhood Acute Lymphoblastic Leukemia: Results of the Randomized Acute Lymphoblastic Leukemia Intercontinental-Berlin-Frankfurt-Münster 2009 Trial

Purpose: The International Berlin-Frankfurt-Münster (BFM) study group conducted a study on pediatric acute lymphoblastic leukemia (ALL). Minimal residual disease (MRD) was assessed using flow cytometry (FCM), and the impact of early intensification and methotrexate (MTX) dose on survival was evaluated. Patients and methods: We included 6,187 patients younger than 19 years. MRD by FCM refined the risk group definition previously used in the ALL intercontinental-BFM 2002 study on the basis of age, WBC count, unfavorable genetic aberrations, and treatment response measured morphologically. Patients at intermediate risk (IR) and high risk (HR) were randomly assigned to protocol augmented protocol I phase B (IB) versus IB regimen. MTX doses of 2 versus 5 g/m2 every 2 weeks, four times, were evaluated in precursor B-cell-ALL (pcB-ALL) IR. Results: The 5-year event-free survival (EFS ± SE) and overall survival (OS ± SE) rates were 75.2% ± 0.6% and 82.6% ± 0.5%, respectively. Their values in risk groups were standard risk (n = 624), 90.7% ± 1.4% and 94.7% ± 1.1%; IR (n = 4,111), 77.9% ± 0.7% and 85.7% ± 0.6%; and HR (n = 1,452), 60.8% ± 1.5% and 68.4% ± 1.4%, respectively. MRD by FCM was available in 82.6% of cases. The 5-year EFS rates in patients randomly assigned to protocol IB (n = 1,669) and augmented IB (n = 1,620) were 73.6% ± 1.2% and 72.8% ± 1.2%, respectively (P = .55), while those in patients receiving MTX doses of 2 g/m2 (n = 1,056) and MTX 5 g/m2 (n = 1,027) were 78.8% ± 1.4% and 78.9% ± 1.4%, respectively (P = .84). Conclusion: The MRDs were successfully assessed using FCM. An MTX dose of 2 g/m2 was effective in preventing relapse in non-HR pcB-ALL. Augmented IB showed no advantages over the standard IB. Unlabelled: [Media: see text]

International cooperative study identifies treatment strategy in childhood ambiguous lineage leukemia

open47siDespite attempts to improve the definitions of ambiguous lineage leukemia (ALAL) during the last 2 decades, general therapy recommendations are missing. Herein, we report a large cohort of children with ALAL and propose a treatment strategy. A retrospective multinational study (International Berlin-Frankfurt-Munster Study of Leukemias of Ambiguous Lineage [iBFM-AMBI2012]) of 233 cases of pediatric ALAL patients is presented. Survival statistics were used to compare the prognosis of subsets and types of treatment. Five-year event-free survival (EFS) of patients with acute lymphoblastic leukemia (ALL)type primary therapy (80% +/- 4%) was superior to that of children who received acute myeloid leukemia (AML)-type or combined-type treatment (36% +/- 7.2% and 50% +/- 12%, respectively). When ALL-or AML-specific gene fusions were excluded, 5-year EFS of CD19(+) leukemia was 83% +/- 5.3% on ALL-type primary treatment compared with 0% +/- 0% and 28% +/- 14% on AML-type and combined-type primary treatment, respectively. Superiority of ALL-type treatment was documented in single-population mixed phenotype ALAL (using World Health Organization and/or European Group for Immunophenotyping of Leukemia definitions) and bilineal ALAL. Treatment with ALL-type protocols is recommended for the majority of pediatric patients with ALAL, including cases with CD19(+) ALAL. AML-type treatment is preferred in a minority of ALAL cases with CD19(-) and no other lymphoid features. No overall benefit of transplantation was documented, and it could be introduced in some patients with a poor response to treatment. As no clear indicator was found for a change in treatment type, this is to be considered only in cases with >= 5% blasts after remission induction. The results provide a basis for a prospective trial.openHrusak, Ondrej; De Haas, Valerie; Stancikova, Jitka; Vakrmanova, Barbora; Janotova, Iveta; Mejstrikova, Ester; Capek, Vaclav; Trka, Jan; Zaliova, Marketa; Luks, Ales; Bleckmann, Kirsten; Möricke, Anja; Irving, Julie; Konatkowska, Benigna; Alexander, Thomas B.; Inaba, Hiroto; Schmiegelow, Kjeld; Stokley, Simone; Zemanova, Zuzana; Moorman, Anthony V.; Rossi, Jorge Gabriel; Felice, Maria Sara; Dalla-Pozza, Luciano; Morales, Jessa; Dworzak, Michael; Buldini, Barbara; Basso, Giuseppe; Campbell, Myriam; Cabrera, Maria Elena; Marinov, Neda; Elitzur, Sarah; Izraeli, Shai; Luria, Drorit; Feuerstein, Tamar; Kolenova, Alexandra; Svec, Peter; Kreminska, Olena; Rabin, Karen R.; Polychronopoulou, Sophia; Da Costa, Elaine; Marquart, Hanne Vibeke; Kattamis, Antonis; Ratei, Richard; Reinhardt, Dirk; Choi, John K.; Schrappe, Martin; Stary, JanHrusak, Ondrej; De Haas, Valerie; Stancikova, Jitka; Vakrmanova, Barbora; Janotova, Iveta; Mejstrikova, Ester; Capek, Vaclav; Trka, Jan; Zaliova, Marketa; Luks, Ales; Bleckmann, Kirsten; Möricke, Anja; Irving, Julie; Konatkowska, Benigna; Alexander, Thomas B.; Inaba, Hiroto; Schmiegelow, Kjeld; Stokley, Simone; Zemanova, Zuzana; Moorman, Anthony V.; Rossi, Jorge Gabriel; Felice, Maria Sara; Dalla-Pozza, Luciano; Morales, Jessa; Dworzak, Michael; Buldini, Barbara; Basso, Giuseppe; Campbell, Myriam; Cabrera, Maria Elena; Marinov, Neda; Elitzur, Sarah; Izraeli, Shai; Luria, Drorit; Feuerstein, Tamar; Kolenova, Alexandra; Svec, Peter; Kreminska, Olena; Rabin, Karen R.; Polychronopoulou, Sophia; Da Costa, Elaine; Marquart, Hanne Vibeke; Kattamis, Antonis; Ratei, Richard; Reinhardt, Dirk; Choi, John K.; Schrappe, Martin; Stary, Ja