ALBERT

Description: Constitutive activation of the FMS-related tyrosine kinase-3 (FLT3) is a common feature of acute leukemias which can be caused by activating mutations or by high expression levels. Aberrant FLT3 downstream signaling is mediated via the RAS/MAPK, PI-3-Kinase/AKT, and STAT5 pathways leading to proliferation, survival, and therapy resistance. In MLL-rearranged acute lymphoblastic leukemia (ALL) activating FLT3 tyrosine kinase domain mutations (TKDs) affecting codons D835 and I836 are frequently identified (Armstrong et al., 2003; Taketani et al., 2004). In addition, MLL-rearranged ALLs are consistently characterized by an exceptionally high FLT3 expression (Armstrong et al., 2002) which has been shown to be associated with ligand independent signaling (Stam et al., 2005). However, the prognostic impact of a constitutive activation of FLT3 in this ALL subset remains controversial. Here, we report on the FLT3 mutational status and gene transcription levels in a large cohort of 95 infants and 72 children with MLL-rearranged ALL. Results obtained were further complemented by a high resolution melting (HRM) screen for common activating NRAS and KRAS mutations at codons 12, 13, and 61. All patients were enrolled in the multicenter trials ALL-BFM 86, 90, 95, 2000, and AIEOP-BFM ALL 2009 as well as Interfant-99 and Interfant-06. In infants, FLT3-TKD mutations were identified in 12/95 patients (12.6%) including one novel insertion/deletion involving codons D835 to S838. In only 2/95 patients (2.1%) an alteration in the juxtamembrane domain of FLT3 was detected. Of the 12 infants with mutation only 2 suffered from a relapse, 2-years cumulative incidence of relapse (CIR) 18%± 12%. In children, only one FLT3 aberration (FLT3-TKD D835 mutation) was detected (1/72, 1.4%). FLT3 transcript levels were analyzed by quantitative real-time PCR in 124 patients (69 infants and 55 children) with available RNA. When we separated the infant cohort into two groups according to the median RQ value, FLT3high and FLT3low, the CIR was significantly different (CIR 19%±7% vs. 66%± 9%, Gray p=0.0001). Of the 6 patients with low FLT3 transcription level, but with presence of a mutation, only one had a relapse. These results indicate that activating FLT3 mutations may compensate for the high relapse risk of patients with a low FLT3 expression. Accordingly, we could show that the CIR was significantly reduced for infants with a low FLT3activation (low transcription, no mutation 19%±7%) compared to those with a high FLT3 activation (high transcription or mutation 75%±9%, Gray p

Description: High-level expression of the cytokine receptor-like factor 2 gene, CRLF2, in precursor B-cell acute lymphoblastic leukemia (pB-ALL) was shown to be caused by a translocation involving the IGH@ locus or a deletion juxtaposing CRLF2 with the P2RY8 promoter. To assess its possible prognostic value, CRLF2 expression was analyzed in 555 childhood pB-ALL patients treated according to the Acute Lymphoblastic Leukemia Berlin-Frankfurt-Münster 2000 (ALL-BFM 2000) protocol. Besides CRLF2 rearrangements, high-level CRLF2 expression was seen in cases with supernumerary copies of the CRLF2 locus. On the basis of the detection of CRLF2 rearrangements, a CRLF2 high-expression group (n = 49) was defined. This group had a 6-year relapse incidence of 31% plus or minus 8% compared with 11% plus or minus 1% in the CRLF2 low-expression group (P = .006). This difference was mainly attributable to an extremely high incidence of relapse (71% ± 19%) in non–high-risk patients with P2RY8-CRLF2 rearrangement. The assessment of CRLF2 aberrations may therefore serve as new stratification tool in Berlin-Frankfurt-Münster–based protocols by identifying additional high-risk patients who may benefit from an intensified and/or targeted treatment.

Description: Abstract 131 Introduction. Autologous stem cell transplantation (ASCT) after cytoreductive induction is considered standard of care for younger patients (pts) with multiple myeloma (MM). The previous standard of induction, the Vincristin-Adriamycin-Dexamethasone (VAD) combination, achieves inferior results compared with induction regimens which combine the proteasome inhibitor Velcade (V = Bortezomib) with Dexamethasone (D)(=VD) and a cytostatic drug such as Doxorubicin (PAD = VD plus Doxorubicin). Velcade-based induction therapy was shown to translate into better myeloma control after high dose melphalan and to lead to prolonged progression-free survival. In order to find a more efficacious and safer drug combination for induction therapy in MM, we tested the combination of Velcade with Cyclophosphamide and Dexamethasone (VCD). Methods. This trial was designed as an open, prospective, multi-center, uncontrolled, combined phase II/III study. As previously reported (Kropff M et al., Ann Hematol 2009), in the first 30 pts the optimal dose of iv Cyclophosphamide in combination with V and D was defined as 900 mg/m2 on d1. Between 03/2006 and 03/2009 we enrolled an additional 370 pts up to 60 years of age with untreated MM to receive three 3-week cycles of induction treatment with V 1.3 mg/m2 iv d1,4,8,11; D 40 mg/d orally d1,2,4,5,8,9,11,12; and C 900mg/m2 iv d1 before scheduled high dose melphalan and ASCT. The primary endpoint of the study is response rate on day 63 after 3 cycles of VCD according to EBMT and IMWG criteria. Results. Final data from 400 pts from 39 German centers will be presented at the meeting. In the currently evaluable 300 pts (mean age 52.3 years; 1.7% stage I, 21.3% stage II, 77.0% stage III) molecular cytogenetic analysis showed a prevalence of 13q- in 38%, of t[4;14] in 13% and of 17p- in 12% of pts (no changes in 35%). All 300 pts (88.3% of whom completed three cycles) were included in the intent-to-treat analysis. Overall response rate (ORR = CR+PR) was 84%, with 10% CR and 74% PR, 5.7% MR, 7.3% NC and 2.3% PD. The negative prognostic impact of 13q- or t[4;14] was abrogated (ORR normal 87.3%, 13q- 83.7%, t[4;14] 90.0%), the unfavorable influence of p53 loss in the 17p- subgroup was still detectable (ORR 69.2%) but this did not reach statistical significance. VGPR rates will be reported at the meeting. Serious adverse events were documented in 78/300 (26.0%) patients. Death rate was remarkably low (1.3%, of which one was not related to the trial medication). 155/300 (52%) of pts experienced grade 3/4 non-serious AEs and of these leucopenia (93/300 pts= 31%), thrombocytopenia (7%), neutropenia (6%), anaemia (5%) were the most frequent events. 80 AEs grade 3 or 4 and 45 SAEs were of infectious origin and occurred in 47/300 pts. 80/130 SAEs (61.5%) were at least possibly related to Velcade. 101/300 pts (34%) developed episodes of peripheral neuropathy. PNP was grade 1 in 62/300 pt (20.7%), grade 2 in 31/300 pt (10.3%) and grade 3 in 7/300 pts (2.3%). Conclusion. This analysis demonstrates that proteasome inhibition by Velcade in combination with Dexamethasone and iv Cyclophosphamide (VCD) is an induction regimen for newly diagnosed MM which is highly effective in a short period of time, has a rather low toxicity profile and is feasible for administration in an outpatient setting. Based on these characteristics, VCD qualifies to become a new standard for MM induction therapy. Disclosures: Einsele: OrthioBiotech: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Off Label Use: Bortezomib is licensed as monotherapy for use in relapsed/refractory MM and in combination with melphalan/Prednisone in the first-line treatment of MM pts ineligible for HD-MEL and ASCT. . Liebisch:OrthoBiotech: Consultancy, Honoraria. Langer:OrthoBiotech: Consultancy. Kropff:OrthoBiotech: Consultancy, Honoraria. Kröger:OrthoBiotech: Honoraria. Ostermann:OrthoBiotech: Honoraria. Mügge:OrthoBiotech: Honoraria. Wolf:OrthoBiotech: Honoraria. Gramatzki:OrthoBiotech: Consultancy, Honoraria. Maschmeyer:OrthoBiotech: Travel Grant. Sezer:OrthoBiotech: Consultancy, Honoraria. Heidemann:OrthoBiotech: Honoraria. Jäger:OrthoBiotech: Honoraria. Dechow:Celgene: Research Funding. Simon:OrthoBiotech: Honoraria. Straka:OrthoBiotech: Consultancy, Honoraria, Research Funding. Fingerle-Rowson:orthoBiotech: Employment. Knop:OrthoBiotech: Honoraria.

Description: ABL-class fusions other than BCR-ABL1 (or Ph+) are found in 2-3% of precursor B-cell acute lymphoblastic leukemia (pB-ALL) in children and adolescents. Occasional reports suggest that this rare ALL subtype has a poor prognosis and patients can benefit from treatment with tyrosine kinase inhibitors (TKIs). Aim of this retrospective study is to investigate the presenting features, treatment response and outcome in ABL-class fusion positive cases identified within large cohorts of patients treated in AIEOP-BFM ALL trials. This retrospective survey of ABL-class fusion positive pB-ALL other than Ph+ ALL was performed in patients aged 1-17 years at the diagnosis, treated from October 2000 to August 2018 according to the AIEOP-BFM (Associazione-Italiana- di- Ematologia-Oncologia Pediatrica-Berlin-Frankfurt-Münster) ALL 2000 and 2009 protocols in Austria, Australia, Czech Republic, Germany, Israel, Italy and Switzerland. While ABL-class fusions screening was not required by protocols, it was performed in some patients, according to centers' policies, usually after poor early treatment response. Overall, 46 ABL-class fusion positive cases with ABL1 fusions (N=15), ABL2 fusions (N=5), CSF1R fusions (N=3) and PDGFRB rearrangements (N=23) were identified. Compared with other pB-ALL children and adolescents, the ABL-class fusion positive cases presented with higher proportions of patients aged 10 years or older (52.2 vs. 22.2, P〈 .0001), hyperleukocytosis (WBC ≥100x109/l, 41.3 vs. 6.3, P〈 .0001), or poor minimal residual disease (MRD) response (〉5x10-4 levels were observed in 65.2% vs. 18%, P〈 .0001 of patients after induction treatment phase IA and in 45.7% vs. 4.8%, P〈 .0001 after consolidation phase IB). For the entire cohort of 46 cases, the 5-year probability of event-free survival (EFS) was 49.1+8.9% and that of overall survival (OS) 69.6+7.8%; the cumulative incidence of relapse (CI) was 25.6+8.2% and treatment-related mortality 20.8+6.8%. Although not prescribed by the protocols, 13 patients received a TKI during different phases of treatment (TKI group), by choice of treating physicians, generally due to poor early treatment response. Eight TKI patients with high MRD levels at the end of induction phase IA received the TKI during consolidation phase IB, and six of them achieved either a low positive or negative MRD level at the end of consolidation phase IB. Nine of the 13 patients treated with TKIs underwent hematopoietic stem cell transplantation (HSCT) and only 1/9 (TKI+HSCT) relapsed. Thirty-three cases did not receive any TKI (no-TKI group) and eight of them relapsed; 6/17 patients treated with chemotherapy only, versus only 2/16 who underwent HSCT. Overall, 25 patients underwent HSCT, and of them 3 relapsed and 6 died of treatment-related complications. In patients with a WBC higher or lower than 100x109/L, the 5-year EFS was 36.8+12.7% vs. 59.9+11.6%, respectively (P= .21), and the 5-year OS was significantly lower in patients with a high WBC (48.8+12.9% vs. 87.4+6.8%, P= .036). This difference was more pronounced in the no-TKI group with a 5-year EFS 27.8+13.6% vs 61.8+12.7%, (P= .07), and an OS of 36.7+14.6% vs 94.4+5.4%, respectively (P= .0015). Presenting features, treatment response and outcome in this cohort of ABL-class fusion positive patients are markedly similar to those of patients with Ph+ ALL included in the EsPhALL studies. Our results suggest that TKIs and HSCT may be beneficial in reducing the risk of relapse. Thus there is an urgent need for large international cooperative controlled studies to investigate the impact of TKI, in combination with an appropriate chemotherapy backbone and the role of HSCT. To this purpose, an early identification of patients with ABL-class fusion positive acute lymphoblastic leukemia will be necessary. Disclosures Izraeli: sightdx: Consultancy; novartis: Honoraria; prime oncology: Speakers Bureau. Locatelli:Miltenyi: Honoraria; bluebird bio: Consultancy; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bellicum: Consultancy, Membership on an entity's Board of Directors or advisory committees. White:BMS: Honoraria, Research Funding; AMGEN: Honoraria, Speakers Bureau. Schrappe:Together with study group from SHIRE, JazzPharma, Servier, SigmaTau, Amgen, and Novartis.: Research Funding; SHIRE, Servier, and JazzPharma: Honoraria.

Description: Abstract 332 PURPOSE : In Multiple Myeloma (MM), the combination of serum beta-2-microglobulin level with serum albumin concentration has been proposed as an outcome predictor in the International Staging System (ISS). More recently, subgroups of MM defined by genetic and cytogenetic abnormalities have been associated with unique biologic, clinical, and prognostic features. PATIENTS AND METHODS: We analyzed the prognostic value of 12 chromosomal abnormalities by fluorescent in situ hybridization (FISH) in a series of 354 MM patients treated within the HOVON-65/GMMG-HD4 trial. Patients with newly diagnosed MM were randomized to receive either three cycles of VAD (arm A; vincristine, adriamycin, dexamethasone) or PAD (arm B; bortezomib, adriamycin, dexamethasone). All patients underwent autologous stem cell transplantation (ASCT) followed by maintenance therapy with thalidomide 50 mg daily (arm A) or bortezomib 1.3 mg/m2 once every 2 weeks (arm B), respectively. In addition, a second cohort of patients was analyzed as a control group (n=462), undergoing ASCT at the University of Heidelberg between September 1994 and December 2010. RESULTS: For the entire group of patients treated within the HOVON-65/GMMG-HD4 trial, we identified 233 patients with 2 copies (67.7%), 95 patients with 3 copies (27.6%) and 16 patients (4.7%) with more than three copies of the chromosomal region 1q21. In addition to del(17p13) and t(4;14), we added +1q21 (〉3 copies) to the group of high-risk aberrations, since the outcome of these patients was almost as poor as it was observed for patients with del(17p13). Subsequently, we analyzed whether combining the ISS score with information on the presence of high-risk aberrations could improve the prognostic value with regard to patients' outcome. A combination of the presence or absence of del(17p13), t(4;14), or +1q21 (〉3 copies) with the ISS score allowed patients to be stratified into three distinct groups: low-risk [absence of del(17p13)/t(4;14)/+1q21 (〉3 copies) and ISS I], high-risk [presence of del(17p13)/t(4;14)/+1q21 (〉3 copies) and ISS II/III], and intermediate-risk (all remaining patients). Most of the patients belonged to the low- (33%) and intermediate-risk (49%) groups, whereas 18% were allocated to the high-risk group. The median PFS times for the low-, intermediate-, and high-risk groups were 41.9 months, 31.1 months (HR=1.7; p=0.0018) and 18.7 months (HR=3.6; p

Description: Technical advances in the field of genomic analyses have stimulated a large number of discovery studies on etiological and clinical endpoints in acute lymphoblastic leukemia (ALL) to provide new avenues for preventive strategies, diagnostics and treatment. Recently, deletion of IKZF1 (IKZF1del) was described as a poor prognostic factor in pediatric ALL (Mullighan CG et al., 2012). In our trial AIEOP-BFM ALL 2000 patients with IKZF1del had a lower 5-year event-free survival (EFS; 0.69±0.05 vs. 0.85±0.01; P

Description: Acute lymphoblastic leukemia (ALL) is the most common malignancy in children and adolescents. Children with Down syndrome (trisomy 21) have a 30-times higher risk of acquiring ALL and pose up to 5% of all pediatric ALL patients. Moreover, many Down syndrome-ALL patients (DS-ALL) suffer from severe toxicity during chemotherapy, especially after application of high dose methotrexate (HD-MTX). Severe toxicities often result in MTX dose reduction, which may be associated with a higher probability of relapse. Systematic and comprehensive toxicity data in a large cohort of uniformly treated DS-ALL patients are lacking. In order to extend our knowledge on MTX-associated toxicities in DS-ALL, we analyzed clinical data from 103 DS-ALL and 1109 Non-DS-ALL (NDS-ALL) patients diagnosed between 1995 and 2016 treated according to German ALL-BFM protocols (ALL-BFM 1995, ALL-BFM 2000 and AIEOP-BFM ALL 2009). We only included patients for whom both therapy and toxicity data were available. We focused on toxicity after HD-MTX administration during the 8-week HD-MTX consolidation in which patients receive 4 courses of intravenous HD-MTX (5 g/m2 each) plus intrathecal MTX in addition to 6-mercaptopurine (25 mg/m2/d). As of 2004, it was recommended for DS-ALL to administer the first MTX course with a reduced dose of 0.5 g/m2 and subsequently increase the dose if no severe toxicity occurs. Toxicity grading was performed according to CTC 2.0. From the 103 DS-ALL patients four switched to high risk treatment and in one patient only incomplete data on toxicity were available. For these patients data could not be analyzed throughout the complete consolidation therapy. From the remaining 98 patients, 42 (43%) received MTX in a dose of 5 g/m2 ± 10%, six (6%) in a dose between 0.551 - 4.499 g/m2 and50 (51%) received a dose of 0.5 g/m2 ± 10% in the first MTX-block. In contrast, 1061 of 1109 (96%) NDS-ALL received an MTX dose of 5 g/m2. One DS-ALL patient died due to a severe infection after the second MTX block and in two DS-ALL patients HD-MTX consolidation was stopped due to severe infections after the first and the third MTX block, respectively. In contrast, HD-MTX was stopped for two NDS-ALL patients due to toxicity (neurotoxicity and infection) after the second and third course, respectively. All five patients received a first MTX dose of 5 g/m2. No NDS-ALL patient died during HD-MTX therapy. After receiving an MTX dose of 5 g/m2 DS-ALL showed significantly higher rates of grade 3/4 leukopenia, stomatitis, thrombocytopenia and infections as compared to NDS-ALL after the first course (Figure A). Reduction of the initial MTX dose to 0.5 g/m2 significantly reduced the rate of stomatitis, thrombocytopenia and leukopenia in DS-ALL by more than 40% (Figure B). However, these patients still suffered significantly more often from grade 3/4 stomatitis and infections compared to NDS-ALL who received full dose MTX (Figure C). Moderate MTX dose escalation for DS-ALL who tolerated a low MTX dose in the first course and received a higher MTX dose in the second course (median MTX dose 1 g/m2) did not result in an increased rate of toxicity as compared to the first course. Importantly, for DS-ALL a reduced MTX dose of 0.5 g/m2 in the first MTX block was not associated with a higher five year-cumulative risk of relapse (CIR) compared to a dose of 5 g/m2 (CIR 0.08±.05 vs. 0.16±0.05, p=.37). Differences in MTX plasma levels at 42 h and 48 h after start of the MTX infusion did not explain the higher rate of toxicity in DS-ALL as compared to NDS-ALL as most DS-ALL patients who received a low MTX dose presented with significantly lower MTX plasma level than NDS-ALL controls who received high dose MTX (Figure D). Additionally, DS-ALL with MTX plasma levels lower than median level (

Description: BACKGROUND Deletions in IKZF1 are found in approximately 15% of children with B-cell precursor acute lymphoblastic leukemia (BCP-ALL). There is strong evidence for the poor prognosis of the most common IKZF1 deletions affecting exons 4-7 (DEL 4-7) and exons 1-8 (DEL 1-8), but evidence for the remaining 33% of cases harboring other variants of IKZF1 deletions is lacking. In an international multi-centre study we analyzed the prognostic value of these rare variants. METHODS Multiplex ligation-dependent probe amplification (MLPA) assays were performed on genomic DNA from patients’ bone marrow aspirates at diagnosis by the national study groups. Each IKZF1-deleted case was matched to three wild-type controls based on cytogenetic subtype, treatment protocol, stratification arm, white blood cell count and age at diagnosis. Known high-risk factors age