scholarly journals Prognostic Impact of MYD88 L265P Mutation By Droplet Digital PCR in IgM MGUS and Smoldering Waldenström Macroglobulinemia

Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 462-462
Author(s):  
David F. Moreno ◽  
Sara Paz ◽  
Mari-Pau Mena ◽  
Monica Lopez-Guerra ◽  
Aina Oliver-Caldes ◽  
...  

Abstract BACKGROUND: MYD88 L265P mutation is highly prevalent in IgM monoclonal gammopathy of undetermined significance (MGUS), smoldering Waldenström macroglobulinemia (SWM) and symptomatic WM. Allele-specific PCR (AS-PCR) has been used routinely to assess MYD88 mutation; however, with the advent of more precise high-throughput technologies such as droplet digital PCR (ddPCR), absolute quantification can be achieved. There is no data regarding ddPCR applicability in asymptomatic IgM monoclonal gammopathies or as a prognostic biomarker. Here, we aimed to compare MYD88 quantification by ddPCR with clinical and laboratory features and to analyze the prognostic impact in a series of patients (pts) with IgM MGUS and SWM. METHODS: We analyzed bone marrow (BM) and peripheral blood (PB) samples stored from pts diagnosed with IgM MGUS and SWM at our institution from 1980 to 2020. DNA extraction methods followed manufacturer instructions (Qiagen) to obtain genomic DNA from unsorted BM samples and cell-free DNA (cfDNA) from PB. MYD88 L265P mutation was quantified by ddPCR using a Bio-Rad commercial assay (HEX-labeled wild-type allele; FAM-labeled mutant allele). We used OCI-Ly3 DLBCL ABC cell line, homozygous for MYD88 L265P, as a positive control. ddPCR was performed following Bio-Rad technical specifications using the QX200 droplet reader. Data was analyzed using QuantaSoft v.1.0 software (Bio-Rad). Absolute quantification of the mutation was expressed as percentage of fractional abundance. For survival analysis, we used a competing risk analysis to evaluate the prognostic impact of MYD88 mutation on progression to symptomatic WM. RESULTS: A total of 217 unsorted samples were analyzed (187 BM and 30 PB). Genomic DNA from unsorted BM samples was extracted from pts diagnosed with IgM MGUS (46%), SWM (44%), and symptomatic WM (10%). cfDNA was obtained from a subgroup of pts with IgM MGUS (52%) and SWM (48%). Median age at diagnosis was 68 (range 61 to 76). AS-PCR could detect the mutation in 22 (31%) pts with IgM MGUS and 49 (75%) with SWM. ddPCR improved precision detection up to 48 (55%) pts with IgM MGUS and 68 (83%) with SWM. All pts with symptomatic WM harbored the MYD88 mutation, as identified by both techniques. Median absolute quantification from BM was 2.3% and 7% for pts with IgM MGUS and SWM, respectively (p<0.001). Pearson correlation coefficients comparing BM MYD88 mutation quantification by ddPCR with serum M-protein size, IgM concentration, BM lymphoplasmacytic infiltration rate and BM CD19+ cells were 0.3, 0.4, 0.6, and 0.9 (p<0.0004), respectively. Similar coefficients were observed in symptomatic WM regarding BM infiltration rate (0.6; p=0.001) and BM CD19+ cells (0.9; p<0.0001). Spearman correlation coefficients comparing cfDNA MYD88 mutation quantification with BM lymphoplasmacytic infiltration rate and BM CD19+ cells were 0.4 and 0.5 (p<0.008), respectively. Agreement regarding MYD88 mutation detection by ddPCR in BM DNA and cfDNA samples was 82% (Cohen kappa index 0.6). With a median overall survival of 13 years in pts with IgM MGUS and SWM, 13% of them progressed to symptomatic WM while 22% died without progression. Cox univariate analysis using continuous values for MYD88 quantification (p=0.004), serum IgM (p<0.001), BM lymphoplasmacytic infiltration (p<0.001), and serum albumin (p=0.04) were significant. X-tile software was used to find the optimal cutoff point of MYD88 quantification as a biomarker. 4.5% was established for pts with IgM MGUS while 25% for SWM. Using the Fine and Gray regression model in a competing risk analysis taking death without progression as a competing event, higher MYD88 mutation burden negatively impacted the risk of progression of IgM MGUS (SHR 4.6; p=0.003) and SWM (SHR 6; p<0.001) (Figure 1). CONCLUSION: Quantification of the MYD88 L265P mutation by ddPCR has higher precision and sensitivity compared to AS-PCR; thus ddPCR could be used as a potential new and useful biomarker. MYD88 tumor burden correlated with well-known laboratory parameters used for diagnosis and risk stratification, whether using genomic DNA from unsorted BM samples or cfDNA. Risk of progression was higher in patients harboring an increased mutant allele burden. This is the first report showing the prognostic impact of MYD88 quantification in a series of patients with asymptomatic IgM gammopathy and long-term follow up. Figure 1 Figure 1. Disclosures Cibeira: Akcea: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees. Bladé Creixenti: Janssen, Celgene, Takeda, Amgen and Oncopeptides: Honoraria. Rosinol: Janssen, Celgene, Amgen and Takeda: Honoraria. Fernandez de Larrea: BMS: Consultancy, Honoraria, Research Funding; Amgen: Consultancy, Honoraria, Research Funding; Takeda: Honoraria, Research Funding; GSK: Honoraria; Sanofi: Consultancy; Janssen: Consultancy, Honoraria, Research Funding.

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 1527-1527
Author(s):  
Sara Rodríguez ◽  
Cirino Botta ◽  
Jon Celay ◽  
Ibai Goicoechea ◽  
Maria J Garcia-Barchino ◽  
...  

Background: Although MYD88 L265P is highly frequent in WM, by itself is insufficient to explain disease progression since most cases with IgM MGUS also have mutated MYD88. In fact, the percentage of MYD88 L265P in CD19+ cells isolated from WM patients is typically <100%, which questions if this mutation initiates the formation of B-cell clones. Furthermore, a few WM patients have detectable MYD88 L265P in total bone marrow (BM) cells and not in CD19+ selected B cells, raising the possibility that other hematopoietic cells carry the MYD88 mutation. However, no one has investigated if the pathogenesis of WM is related to somatic mutations occurring at the hematopoietic stem cell level, similarly to what has been shown in CLL or hairy cell leukemia. Aim: Define the cellular origin of WM by comparing the genetic landscape of WM cells to that of CD34 progenitors, B cell precursors and residual normal B cells. Methods: We used multidimensional FACSorting to isolate a total of 43 cell subsets from BM aspirates of 8 WM patients: CD34+ progenitors, B cell precursors, residual normal B cells (if detectable), WM B cells, plasma cells (PCs) and T cells (germline control). Whole-exome sequencing (WES, mean depth 74x) was performed with the 10XGenomics Exome Solution for low DNA-input due to very low numbers of some cell types. We also performed single-cell RNA and B-cell receptor sequencing (scRNA/BCRseq) in total BM B cells and PCs (n=32,720) from 3 IgM MGUS and 2 WM patients. Accordingly, the clonotypic BCR detected in WM cells was unbiasedly investigated in all B cell maturation stages defined according to their molecular phenotype. In parallel, MYD88p.L252P (orthologous position of the human L265P mutation) transgenic mice were crossed with conditional Sca1Cre, Mb1Cre, and Cγ1Cre mice to selectively induce in vivo expression of MYD88 mutation in CD34 progenitors, B cell precursors and germinal center B cells, respectively. Upon immunization, mice from each cohort were necropsied at 5, 10 and 15 months of age and screened for the presence of hematological disease. Results: All 8 WM patients showed MYD88 L265P and 3 had mutated CXCR4. Notably, we found MYD88 L265P in B cell precursors from 1/8 cases and in residual normal B cells from 3/8 patients, which were confirmed by ASO-PCR. In addition, CXCR4 was simultaneously mutated in B cell precursors and WM B cells from one patient. Overall, CD34+ progenitors, B-cell precursors and residual normal B cells shared a median of 1 (range, 0-4; mean VAF, 0.16), 2 (range, 1-5; mean VAF, 0.14), and 4 (range, 1-13; mean VAF, 0.26) non-synonymous mutations with WM B cells. Some mutations were found all the way from CD34+ progenitors to WM B cells and PCs. Interestingly, concordance between the mutational landscape of WM B cells and PCs was <100% (median of 85%, range: 25%-100%), suggesting that not all WB B cells differentiate into PCs. A median of 7 (range, 2-19; mean VAF, 0.39) mutations were unique to WM B cells. Accordingly, many clonal mutations in WM B cells were undetectable in normal cells. Thus, the few somatic mutations observed in patients' lymphopoiesis could not result from contamination during FACSorting since in such cases, all clonal mutations would be detectable in normal cells. Of note, while somatic mutations were systematically detected in normal cells from all patients, no copy number alterations (CNA) present in WM cells were detectable in normal cells. scRNA/BCRseq unveiled that clonotypic cells were confined mostly within mature B cell and PC clusters in IgM MGUS, whereas a fraction of clonotypic cells from WM patients showed a transcriptional profile overlapping with that of B cell precursors. In mice, induced expression of mutated MYD88 led to a moderate increase in the number of B220+CD138+ plasmablasts and B220-CD138+ PCs in lymphoid tissues and BM, but no signs of clonality or hematological disease. Interestingly, such increment was more evident in mice with activation of mutated MYD88 in CD34+ progenitors and B-cell precursors vs mice with MYD88 L252P induced in germinal center B cells. Conclusions: We show for the first time that WM patients have somatic mutations, including MYD88 L265P and in CXCR4, at the B cell progenitor level. Taken together, this study suggests that in some patients, WM could develop from B cell clones carrying MYD88 L265P rather than it being the initiating event, and that other mutations or CNA are required for the expansion of B cells and PCs with the WM phenotype. Disclosures Roccaro: Janssen: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Transcan2-ERANET: Research Funding; AstraZeneca: Research Funding; European Hematology Association: Research Funding; Transcan2-ERANET: Research Funding; Associazione Italiana per al Ricerca sul Cancro (AIRC): Research Funding; Associazione Italiana per al Ricerca sul Cancro (AIRC): Research Funding; European Hematology Association: Research Funding; Janssen: Membership on an entity's Board of Directors or advisory committees; AstraZeneca: Research Funding; Amgen: Membership on an entity's Board of Directors or advisory committees. San-Miguel:Amgen, Bristol-Myers Squibb, Celgene, Janssen, MSD, Novartis, Roche, Sanofi, and Takeda: Consultancy, Honoraria. Paiva:Amgen, Bristol-Myers Squibb, Celgene, Janssen, Merck, Novartis, Roche, and Sanofi; unrestricted grants from Celgene, EngMab, Sanofi, and Takeda; and consultancy for Celgene, Janssen, and Sanofi: Consultancy, Honoraria, Research Funding, Speakers Bureau.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 4024-4024
Author(s):  
Michael Lubbert ◽  
Stefan Suciu ◽  
Uwe Platzbecker ◽  
Aristoteles A.N. Giagounidis ◽  
Dominik Selleslag ◽  
...  

Abstract Abstract 4024 Background: The hypomethylating agents 5-azacytidine (Vidaza) and 5-aza-2′-deoxycytidine (Decitabine, DAC) are active in different MDS subtypes. Compared to other response predictors to DAC, prior MDS duration has received only limited attention (1, 2), with conflicting results. Based on our finding that long duration of MDS prior to DAC treatment may be a novel factor linked to a better outcome (1), we now assess its value in the phase III trial 06011 (DAC versus BSC [3]). Immediate enrolment after diagnosis was allowed in that trial, median MDS duration prior to randomization thus only 3 months (mths). Methods: Comparison of progression-free (PFS), AML-free (AMLFS) and overall survival (OS) according to MDS duration >= vs. <3 mths in 233 patients (pts) with higher-risk MDS (median age 70 years) randomized to DAC (n=119) or BSC (n=114). Comparisons by long-rank test and multivariate analyses by Cox regression (Performance Status [PS], cytogenetics and IPSS high risk N/Y) were performed retrospectively: MDS duration had not yet been known as possible stratification factor at time of study initiation, and the trial thus not been powered to detect significant differences with regard to this discriminator. Results: A better prognosis of patients with MDS duration >=3 vs <3 mths was observed in DAC arm (B vs A) and BSC arm (D vs C). Conversely, DAC yielded better results than BSC in each MDS duration group: <3 mths (A vs C) and >=3 mths (B vs D). In both arms (n=233), Mult. indicated that MDS duration (>=3 vs <3 mths) adjusted for treatment, PS, cytogenetics and IPSS group was an independent prognostic factor regarding PFS (HR=0.75, 95%CI 0.58–0.99), AMLFS (HR=0.68, 95%CI 0.51–0.90), and OS (HR=0.75, 95%CI 0.56–0.99). The tests for interaction treatment × duration of MDS were not significant for 3 endpoints: PFS (p=0.38), AMLFS (p=0.90), OS (p=0.67). Conclusion: In intermediate-2 and high-risk MDS pts, long duration from MDS diagnosis to start of DAC or BSC appeared to be associated with a better outcome. This finding is in sharp contrast to the adverse prognostic impact of antecedent disease duration in patients who received intensive chemotherapy (4). It is supported by a similar analysis of pts with AML from MDS treated on the 00331 DAC phase II multicenter trial: those with longer MDS duration prior to DAC also had better outcome (5). Application of this discriminator in the evaluation also of other DAC schedules and MDS treatments therefore appears warranted. References: 1. Wijermans et al., Ann. Hematol. 84 (suppl. 1): 9–14, 2005 2. Kantarjian et al., Cancer 109:265-73, 2007 3. Wijermans et al., Blood 112 (suppl. 1): abs. 226, 2008 4. Estey et al., Blood 90:2969-77, 1997 5. Lübbert, Schmoor et al., abstract submitted, ASH 2010 Disclosures: Platzbecker: Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Salih:Pfizer: Research Funding. Muus:Celgene: Membership on an entity's Board of Directors or advisory committees; Alexion: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 782-782
Author(s):  
Alice Fabarius ◽  
Armin Leitner ◽  
Andreas Hochhaus ◽  
Martin C Müller ◽  
Claudia Haferlach ◽  
...  

Abstract Abstract 782 Introduction: Current evidence indicates that acquired genetic instability in chronic myeloid leukemia (CML) as a consequence of the t(9;22)(q34;q11) and the resulting BCR-ABL fusion causes the continuous acquisition of additional chromosomal aberrations (ACA) and mutations and thereby progression to accelerated phase and blast crisis (BC). Around 10 –12% of patients in chronic phase (CP) CML have ACA already at diagnosis. During the course of the disease this number rises to 80% in BC. Acquisition of ACA during treatment is considered as a poor prognostic indicator, whereas the impact of ACA at diagnosis is controversial. Patients and methods: Clinical and cytogenetic data of 1151 out of 1311 patients with Philadelphia and BCR-ABL positive CP CML randomized until 2009 to the German CML-Study IV were investigated in a prospective study. There were 459 females (40%) and 692 males (60%). Median age was 53 years (range, 16–88). All patients were treated with imatinib alone or in combination with interferon alpha or araC. The impact of ACA at diagnosis on time to complete cytogenetic and major molecular remission (CCR, MMR) and progression-free and overall survival (PFS, OS) was investigated. Written informed consent was obtained from all patients prior to entering the study. Results: At diagnosis 1003/1151 patients (87%) had the standard t(9;22)(q34;q11) only and 69 patients (6.0%) had a variant t(v;22). In 60 of 69 patients with t(v;22), only one further chromosome was involved in the translocation, in 7 patients two, and in 2 patients three further chromosomes were involved. Seventy-nine patients (6.9%) had ACA. Of these, 38 patients (3.3%) lacked the Y chromosome (-Y) and 41 patients (3.6%) had ACA except -Y. Sixteen of the 41 patients had major-route ACA (+8, i(17)(q10), +der(22)t(9;22)(q34;q11), ider(22)(q10)t(9;22)(q34;q11)) and 25 minor-route ACA [e.g. t(3;12), t(4;6), t(2;16), t(1;21)]. In patients with major-route ACA, trisomy 8 was the most frequent additional alteration (n=9). +der(22)t(9;22)(q34;q11) was observed in six patients, isochromosome (17)(q10) in five patients and ider(22)(q10)t(9;22)(q34;11) in three patients. After a median observation time of 5.3 years for patients with t(9;22), t(v;22), -Y, minor- and major-route ACA median times to CCR were 1.01, 0.95, 0.98, 1.49 and 1.51 years, to MMR 1.40, 1.58, 1.65, 2.49 and > 7 years, 5-year PFS 90%, 81%, 88%, 96% and 50% and 5-year OS 92%, 87%, 91%, 96% and 53%, respectively. In patients with major-route ACA times to CCR and MMR were longer. PFS and OS were shorter (p<0.001) than with standard t(9;22)(q34;q11). Loss of Y chromosome had no influence on time to CCR or MMR, PFS and OS. Conclusion: We conclude that the prognostic impact of additional cytogenetic findings at diagnosis of CML is heterogeneous and consideration of their types may be important. Major-route ACA identify a small group of patients with significantly poorer prognosis as compared to all other patients requiring early and more intensive intervention such as stem cell transplantation. Disclosures: Hochhaus: Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees; Ariad: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Kneba:Hoffmann La Roche: Honoraria.


Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 1992-1992 ◽  
Author(s):  
Eugen Tausch ◽  
Christina Galler ◽  
Richard Schlenk ◽  
Peter Hillmen ◽  
Fritz Offner ◽  
...  

Abstract BACKGROUND: Genomic aberrations and IGHV mutation status are established prognostic factors in CLL. With TP53, NOTCH1, SF3B1, ATM, MYD88, FBXW7, BIRC3 and POT1 recurrently mutated genes were found in CLL and were discussed to associate with disease characteristics and to affect therapy efficacy and outcome. METHODS: We assessed the incidence and impact of gene mutations in the COMPLEMENT1 trial (1st line Chl vs. O-Chl). Pretreatment samples were available from 376 patients (84.1%) and this cohort was representative of the full trial population. Mutations were analyzed by amplicon-based targeted NGS using Illumina Miseq for all coding exons (TP53, ATM, MYD88, FBXW7, BIRC3 and POT1) or hotspot exons (NOTCH1, SF3B1). Additionally, the exact variant frequency was determined. RESULTS: The incidences of gene mutations were: TP53 8.2%, NOTCH1 14.9%, SF3B1 14.1%, ATM 10.9%, MYD88 2.7%, FBXW7 3.5%, POT1 7.7%, and BIRC3 2.7%. Regarding baseline characteristics, we found significant associations: TP53mut with high ß2MG (p=0.01), 17p- (p<0.01), and unmutated IGHV (p=0.01); ATMmut with high WBC (p=0.02), and 11q- (p<0.01); MYD88mut with mutated IGHV (p=0.02); FBXW7mut with 17p- (p=0.02), and +12q (p<0.01). BIRC3mut was only present in IGHV unmutated cases (p<0.01), was more frequent in 11q- (p<0.01), +12q (p=0.05), and in cases with NOTCH1mut (p=0.05). POT1mut was more frequent in NOTCH1mut cases (p=0.02) without associations with any other baseline parameter. Regarding response to treatment, TP53mut was significantly associated with reduced ORR rate (p<0.01). CR rate was not correlated with mutations in the covered genes. At a median follow-up of 31.7 months, there were 249 (66%) events for PFS and 63 (16.8%) events for OS. O-Chl as compared to Chl resulted in significantly improved PFS (median 22.4 vs. 13.1 months, HR 0.54, p<0.01). In univariate analyses, TP53mut (HR 2.07, p<0.01), NOTCH1mut (HR 1.50, p=0.01) and SF3B1mut (HR 1.66, p=0.01) were associated with shorter PFS, whereas ATM and other candidate genes showed no association (ATMmut: HR 1.40, p=0.07). Analyzing both treatment arms separately, TP53mut had an impact on PFS with Chl and O-Chl treatment (HR 1.92, p=0.04 and HR 2.49, p<0.01). Notably, NOTCH1mut was associated with outcome in O-Chl only (HR 2.01, p<0.01 vs. HR 1.14, p=0.59) resulting in a reduced beneficial effect from the addition of Ofatumumab to Chlorambucil treatment. ATMmut and BIRC3mut mutations were only adverse prognostic factors with Chl monotherapy (ATMmut: HR 1.69, p=0.05 vs. HR 1.35, p=0.27; BIRC3mut: HR 2.84, p=0.04 vs. HR 0.99, p=0.99). OS was reduced significantly only in TP53mut cases (HR 3.69, p<0.01). Of note, none of the MYD88mut cases (n=10) had died within the follow-up period. To identify genomic factors of independent prognostic impact, we performed multivariable Cox regression analyses for PFS and OS including treatment arms, 11q-, +12q, 17p-, IGHV and all candidate gene mutations. For PFS, the following independent prognostic factors were identified: O-Chl (HR 0.46, p<0.01), 17p- (HR 3.14, p<0.01), 11q- (HR 1.57, p=0.01), unmutated IGHV (HR 1.43, p=0.02), TP53mut (HR 1.81, p=0.03), NOTCH1mut (HR 1.63, p<0.01) and SF3B1mut (HR 1.54, p=0.02). Regarding OS, only 17p- (HR 4.07, p<0.01), and unmutated IGHV (HR 1.81, p=0.05) were identified as independent adverse prognostic factors with TP53mut showing a trend (HR 2.14, p=0.10). CONCLUSION: We performed mutational analyses for the 8 most frequent mutated genes in CLL in the COMPLEMENT1 trial evaluating 1st line O-Chl against Chl. An independent prognostic impact was identified for TP53mut, NOTCH1mutand SF3B1mut regarding PFS. Notably, NOTCH1mut affected outcome mainly with O-Chl treatment, whereas ATMmut and BIRC3mut were associated with outcome with Chl monotherapy. In multivariate analysis for OS, none of the gene mutations, but the established parameters IGHV and 17p- had independent prognostic impact. Disclosures Tausch: GlaxoSmithKline: Research Funding, Travel support Other. Hillmen:GSK: Honoraria, Research Funding. Offner:GlaxoSmithKline: Honoraria, Research Funding. Janssens:GSK: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Amgen: Speakers Bureau; Roche: Speakers Bureau; Mundipharma: Speakers Bureau. Mayer:Glaxo: Research Funding; Roche: Research Funding. Panagiotidis:GlaxoSmithKline: Consultancy, Honoraria. McKeown:GlaxoSmithKline: Employment. Gupta:GlaxoSmithKline: Employment. Stilgenbauer:GlaxoSmithKline: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding.


Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 3684-3684
Author(s):  
Connor M. Walsh ◽  
Anthony Hunter ◽  
Terra Lasho ◽  
Christy Finke ◽  
Rami S. Komrokji ◽  
...  

Abstract Introduction: Mutations involving isocitrate dehydrogenase 1/2 (IDH) are known oncogenic drivers in hematological malignancies, conferring neomorphic enzymatic activity to IDH 1/2, resulting in the oncometabolite, 2-hydroxyglutarae (2-HG). 2-HG in turn suppresses TET activity, making IDH and TET2 mutations synthetically lethal and almost mutually exclusive. The frequency of IDH mutations in CMML is &lt;10% and their prognostic impact remains unclear. We carried out this study in a large database of molecularly annotated CMML patients to better define the clinical profile and prognostic impact of these mutations. Methods: After IRB approval, CMML patients from the Mayo Clinic, Minnesota and the Moffitt Cancer Center (MCC), Tampa, Florida, were included in the study. All patients had bone marrow (BM) biopsies with cytogenetics and molecular genetics done either at diagnosis, or at first referral. Clinical and mutational data were abstracted and retrospectively analyzed. Overall survival (OS) was calculated from date of CMML diagnosis to date of death/last follow, while AML-free survival (AML-FS) was calculated from date of CMML diagnosis to date of leukemic transformation (LT). Patients that had undergone allogeneic HCT were excluded from the study (n=3). Statistical analysis was carried out using the Blue Sky software. Results: Six hundred and forty four patients were included in the study (Mayo Clinic-357, MCC- 287), median age 71 years (range, 20-95 years), 67.8% being male. Forty-three (6.7%) patients had IDH mutations, 35 (82%) IDH2 and 8 (18%) IDH1; of which, 34 (97%) involved the IDH2R140 hotspot and 5 (62.5%) involved the IDH1R132 hotspot, respectively. The median variant allele fractions (VAF) for IDH1 mutations was 41% (range, 8-46%) and for IDH2 mutations was 46% (range, 7-70%). There were no significant demographic or clinical differences between IDH mutant and wild type CMML patients, with the exception that IDH mutant CMML patients were less likely to be thrombocytopenic (p=0.006), were less likely to have TET2 co-mutations (14% vs 53.2%; p&lt;0.001) and were more likely to have SRSF2 co-mutations (69.8% VS 40.3%; p&lt;0.001). Importantly there were no differences in proliferative or dysplastic subtypes (p=0.3), cytogenetic (p=0.12) and molecular risk stratifications (p=045). There were also no significant demographic or clinical differences between IDH1 vs IDH2 mutant CMML patients. Six (14%) IDH mutant CMML patients had TET2 co-mutations; 5 (83%) with IDH2R140Q (median VAF-28%;all male) and 1 (17%) with IDH1R132H (VAF-44%;female) (Figure 1). Five (11%) IDH2 mutant patients were treated with enasidenib (IDH2 inhibitor), none with a durable response, while none of the IDH1 mutant patients received targeted therapy. At last follow up (median 18 months), 337 (52%) deaths and 119 (18.5%) LT have been documented, with IDH mutant patients having a higher LT rate (30.2% vs 17.6%, p=0.04) compared to wildtype patients. The median OS of the entire cohort was 35 months, with no difference in OS between IDH mutant and wild type patients (34.5 vs 35 months, p=0.12), with IDH1 mutant patients having a shorter OS in comparison to IDH2 mutant patients (31 vs 37 months; p=0.005- Figure 1). IDH mutant CMML patients also had a shorter AML-FS in comparison to wild type patients (36.6 vs 210 months, p=0.005), with there being no differential impact on AML-FS of IDH1 vs IDH2 mutations (p=0.26, Figure 1). Conclusions: IDH mutations are infrequent in CMML (7%), with IDH2 mutations being more common than IDH1 mutations (80 vs 20%). IDH mutations co-occur very infrequently with TET2 mutations (14%), with IDH mutant patients being less likely to have thrombocytopenia and more likely to have SRSF2 co-mutations. IDH mutations negatively impacting AML-FS without a significant impact on OS. Prospective clinical trials testing the safety and efficacy of IDH1/2 inhibitors in CMML are much needed. Figure 1 Figure 1. Disclosures Komrokji: AbbVie: Consultancy; PharmaEssentia: Membership on an entity's Board of Directors or advisory committees; Taiho Oncology: Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Jazz: Consultancy, Speakers Bureau; Acceleron: Consultancy; BMSCelgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Geron: Consultancy. Al-Kali: Novartis: Research Funding; Astex: Other: Research support to institution. Padron: BMS: Research Funding; Stemline: Honoraria; Taiho: Honoraria; Kura: Research Funding; Incyte: Research Funding; Blueprint: Honoraria. Patnaik: StemLine: Research Funding; Kura Oncology: Research Funding.


Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 957-957
Author(s):  
Yasunobu Nagata ◽  
Hideki Makishima ◽  
Tomas Radivoyevitch ◽  
Cassandra M. Hirsch ◽  
Bartlomiej P Przychodzen ◽  
...  

Abstract Targeted and unbiased next generation sequencing (NGS) has contributed to a better understanding of the molecular pathogenesis of myeloid neoplasms, including MDS. Discovery efforts have identified novel classes of mutated genes, while deep NGS approaches have yielded a better appreciation of clonal hierarchy, inter-case variability and intra-tumor heterogeneity. MDS is a disease continuum characterized by a wide spectrum of often overlapping lesions that determine phenotype, while also serving as initiation and progression events. In addition to somatic lesions, germ line (GL) alterations can serve as bona fidenon-clonal ancestral events that play an underappreciated role in MDS pathogenesis. While some of these lesions are associated with childhood familial leukemia syndromes, others are unknown, and are likely characterized by a low/variable penetrance and delayed disease manifestation. To delineate clonal dynamics in MDS, we sequenced whole exomes of 262 cases with primary MDS and related disorders. For validation and confirmation we also deep sequenced a cohort of 1,686 additional cases with a various type of myeloid malignancies. An extensive bioanalytic pipeline and confirmatory sequencing, including GL DNA analysis, was used to discriminate somatic vs. GL lesions and exclude sequencing artifacts. Initially we focused on driver somatic events in significantly mutated genes. All somatic mutations were subjected to clonal hierarchy analysis using variant allele frequencies (VAFs). In selected cases (n = 180), serial analyses were performed. Using VAF rankings of each event, a position within the clonal hierarchy was assigned; while each patient has a single dominant clone, some may have a founding chromosomal abnormality and others may have VAFs too close to distinguish, i.e. have co-dominant events. In general, multiple subclonal events are detected in each patient. For the purpose of this analysis we distinguished between 2 types of ancestral events: 1) driver non-clonal mutations (e.g., GL TP53, RUNX1, ETV6) and 2) predisposition non-clonal events (FA genes, telomerase genes, BRCA1/2). The latter do not influence the clonal architecture. Based on average sequencing depth, 5,474 somatic mutations were identified: 241 (92%) were clonal dominant and 234 (89%) were sub-clonal (secondary) events. The median number of mutations in subclonal events per case was 13. The number of mutations in subclonal events was higher than that in events that were clonal dominant (4,881 vs 593). No genes were mutated in a purely dominant fashion and some genes were almost entirely subclonal, e.g., RAS and FLT3. For each dominant event, there is a frequent secondary lesion, e.g., dominant TET2 mutations are followed by subclonal second TET2 events, SRSF2 and ASXL1 lesions. Thus, novel relationships between dominant and subclone events were found, indicating the presence of invariant functional interactions among different mutations in MDS pathogenesis. In a confirmatory cohort studied by NGS targeted to a selected panel of significantly mutated genes, the number of subclonal events increased due to greater coverage and thus sensitivity. The spectrum of dominant events, however, should not differ as they are inherently associated with a high clonal burden. For examples, TP53 clonal mutations frequently co-occur with TP53 subclonal mutations (12%, p=.004), but are exclusive of STAG2 subclonal mutations. EZH2 clonal and ASXL1 secondary mutations also co-occur. Classifications of clonal and secondary events may have prognostic and diagnostic implications. We identified a spectrum of novel predisposition and non-clonal driver variants by comparing to ethnically weighted control populations. Eight mutations (3%, 8/262 cases) in 3 genes (DDX41, TP53, and ELANE) were identified as driver non-clonal mutations because identical mutations were reported in familial leukemia syndromes, while 16 mutations (6%) in 3 genes (CSF3R, BRCA1, and RPL5) were identified as non-clonal predisposition events. Detailed understanding of such clonal dynamics and complexity of clonal hierarchical complexity may have clinical significance, both for somatic mutations and for germline events. Increasing clonal burden of extracted genes associated with predictive prognostic impact should be prospectively validated in a more uniform and larger cohort of MDS cases. Disclosures Makishima: The Yasuda Medical Foundation: Research Funding. Mukherjee:Celgene: Consultancy, Honoraria, Research Funding; Novartis: Consultancy, Honoraria, Research Funding; Ariad: Consultancy, Honoraria, Research Funding. Sole:Celgene: Membership on an entity's Board of Directors or advisory committees. Carraway:Celgene: Research Funding, Speakers Bureau; Baxalta: Speakers Bureau; Incyte: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees. Sekeres:Millenium/Takeda: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees. Ogawa:Kan research institute: Consultancy, Research Funding; Sumitomo Dainippon Pharma: Research Funding; Takeda Pharmaceuticals: Consultancy, Research Funding. Maciejewski:Alexion Pharmaceuticals Inc: Consultancy, Honoraria, Speakers Bureau; Apellis Pharmaceuticals Inc: Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Honoraria, Speakers Bureau.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 4028-4028
Author(s):  
Alessandro Levis ◽  
Daniela Maria Gioia ◽  
Laura Godio ◽  
Mauro Girotto ◽  
Bernardino Allione ◽  
...  

Abstract Abstract 4028 BACKGROUND. The corner stone of the WHO classification and prognostic scores of myelodysplastic syndromes (MDS) is the blast count in bone marrow. The standard cytology evaluation of at least 500 bone marrow cells is easy to perform, but some concerns arise about reproducibility of this method. Nowadays bone marrow trephine biopsy and flow cytometry are frequently considered for the diagnosis of MDS. However there is so far paucity of data comparing cytology, histology and flow cytometry in quantifying bone marrow blasts in order to differentiate non RAEB from BAEB-I and RAEB-II cases. AIM OF THE WORK. The Aim of the work was to analyse the differences and the prognostic impact of cytology, histology and flow cytometry in differentiating non RAEB from BAEB-I and RAEB-II. PATIENTS AND METHODS. Since 1999, clinical and laboratory data from 1256 new cases of MDS were prospectively recorded into the Piemonte MDS Registry. Blast count could be performed with the three different methods: BMC (bone marrow cytology) has been performed in 844 cases, BMH (bone marrow histology) in 874 cases, and BMF (bone marrow flow cytometry) in 636. In order to quantify blasts, immune-histochemistry evaluation of CD34+ cells was used in BMH, while both CD34+ and CD117+ cells were considered in BMF. Out of the total of the 636 patients analysed by BMF only 420 had an accurate and complete registration of CD34 and CD117 positivity and were considered for the present analysis. In two hundred and thirty six cases all three evaluations were contemporary available. The concordance of each diagnostic method with the others and their prognostic value were evaluated in both univariate and multivariate analyses. A comparison between BMC and BMH was available in 571 cases, between BMC and BMF in 228 cases, and between BMH and BMF in 279 cases. RESULTS. The disagreement in classifying patients as non-RAEB or RAEB-I or RAEB-II between BMC and BMH was 156/571 (27%), with BMH over-evaluating blasts in 114/571 cases (20%) and under-evaluating blasts in 42/571 cases (7%). The disagreement between BMC and BMF was 80/228 (35%), with BMF over-evaluating and under-evaluating blast percentage in comparison to BMC in 53/228 (23%) and in 27/228 (12%) cases respectively. The disagreement between BMH and BMF was present in 113/279 (41%), with BMF over-evaluating and under-evaluating blast percentage in comparison to BMH in 44/279 (16%) and in 69/279 (25%) cases respectively. In univariate analysis all three methods of quantifing blasts and differentiating non-RAEB from RAEB-I and RAEB-II retained an important prognostic value for both leukemic evolution and survival. However when the three models were tested in multivariate analysis in order to define the best predictor of leukemic evolution, BMC retained the best predictive value. CONCLUSIONS. When BMH or BMF are used instead of BMC in order differentiate non-RAEB from RAEB-I and RAEB-II, the shift to a different WHO category is evident in at least 30% of patients and BMH and BMF do not play the same role as BMC. BMC still remain the standard method to quantify blasts for classification and prognostic evaluation of MDS. Disclosures: Off Label Use: Lenalidomide in Mantle Cell Lymphoma. Boccadoro:Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen-Cilag: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Saglio:Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 305-305 ◽  
Author(s):  
Hartmut Goldschmidt ◽  
Kai Neben ◽  
Uta Bertsch ◽  
Thomas Hielscher ◽  
Bronno van der Holt ◽  
...  

Abstract Abstract 305 Chromosomal aberrations are important prognostic parameters in multiple myeloma (MM). By using interphase fluorescent in situ hybridization (FISH) on CD138-enriched plasma cells, specific changes in interphase cells can be detected, overcoming the lack of dividing cells required for conventional cytogenetics. We evaluated the association of FISH results and outcome of a subgroup of patients (pts) within the HOVON-65/GMMG-HD4 trial, a prospective, randomized phase III trial for pts with newly diagnosed MM stage II or III according to Salmon & Durie up to 65 years. Pts were randomized to receive three cycles of VAD (arm A; vincristine, adriamycin, dexamethasone) or PAD (arm B; bortezomib, adriamycin, dexamethasone). Hematopoietic stem cells were mobilized using the CAD regimen and G-CSF. All pts received one or two cycles of high dose melphalan (200 mg/m2) with autologous stem cell transplantation followed by maintenance therapy with thalidomide 50 mg daily (arm A) or bortezomib 1.3 mg/m2 once every 2 weeks (arm B), respectively, for a maximum of 2 years. Sites in Germany, the Netherlands and Belgium participated in this trial (n=833 pts). For the German pts (GMMG, n=399) FISH was performed in a single laboratory prior to start of treatment. Cytospins of CD138 purified plasma cells were subjected to FISH with two-color probe sets for the detection of numerical changes for the following chromosome regions: 1q21/8p21, 6q21/15q22, 9q34/22q11, 11q23/13q14, and 17p13/19q13, as well as for the translocations t(4;14)(p16;q32), t(11;14)(q13;q32), and t(14;16) (q32;q23). As of July 2010 data from the first consecutively enrolled 626 patients of the trial have been analyzed, including 284 GMMG pts. For this analysis, FISH results from 258 (91%) GMMG pts were available (n=131 in arm A; n=127 in arm B). Patient characteristics in the GMMG subgroup are comparable to the analyzed trial population of 626 pts. For all pts the median follow-up time from randomization was 40.3 months (mo.). The most pronounced impact on prognosis was seen for t(4;14), del17p13, and gain1q21, each significantly associated with poor prognosis with respect to progression free survival (PFS) and overall survival (OS). The strongest prognostic impact was found for del17p13. FISH analysis detected del17p13 in 9.4% of pts (A: 12.3% vs. B: 6.4%), t(4;14) in 14.8 % (16.3% vs. 13.4%), and gain 1q21 in 33.7% of pts (33.1% vs. 34.4%). When comparing pts in the two arms for PFS, we found a borderline significance for the interaction between t(4;14) and treatment arm (p=0.06), indicating that the effect of t(4;14) depends on the treatment. Pts with t(4;14) in arm A show a very poor prognosis with a median PFS time only half as long compared to patients without translocation (18 vs. 36 mo.; p=0.003). No such negative effect was observed for patients in arm B with t(4;14) (36 vs. 40 mo.; p=0.97). PAD resulted in improved 3yr-OS rates for pts with t(4;14) (A:39% vs B:76%), while 3yr-OS was 79% and 87% in pts without t(4;14). Median PFS for pts with gain 1q21 was 22 mo. (arm A) vs. 30 mo. (arm B) compared to 41 mo. in both arms for patients without gain 1q21. Pts with gain 1q21 showed a significantly better OS when treated with bortezomib (3yr-OS rates: A: 59%, B: 83%, p=0.016). Del17p13 was significantly associated with poor prognosis in both arms for OS (A: p<0.0001, B:p=0.01) and PFS (A: p=0.0008, B: 0.07), with pts with del 17p13 in arm B showing higher PFS rates (median PFS of 26 mo.) compared to pts in arm A (median PFS of 13 mo., p=0.35), but based on low pts numbers. In conclusion our analysis confirms the significant negative prognostic impact of del17p13 and gain 1q21 on PFS and OS for pts with newly diagnosed MM. In our analysis, the negative impact of t(4;14) on PFS could almost completely be overcome by the bortezomib-based treatment. Pts with t(4;14) also showed improved OS when treated with bortezomib, but still had an inferior prognosis compared to pts without this cytogenetic aberration. Similarly, bortezomib significantly prolonged OS in patients with gain 1q21 but did only partially overcome the adverse effect of this aberration. The HOVON65/GMMG-HD4 trial (EudraCT nr 2004-000944-26) was supported by the Dutch Cancer Foundation, the German Federal Ministry of Education and Research and a grant from Janssen Cilag. The GMMG also received grants for this trial by Novartis, AMGEN, Chugai, Roche and the Tumorzentrum Heidelberg/Mannheim. Disclosures: Goldschmidt: Ortho Biotech: Honoraria, Research Funding; Amgen: Research Funding; Novartis: Honoraria, Research Funding; Chugai: Honoraria, Research Funding; Roche: Honoraria, Research Funding; Celgene: Honoraria, Research Funding. Off Label Use: bortezomib in newly diagnosed myeloma. Neben:Ortho Biotech: Honoraria; Celgene: Honoraria. Pfreundschuh:Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Membership on an entity's Board of Directors or advisory committees. Duehrsen:Ortho Biotech: Honoraria. Weisel:Ortho Biotech: Consultancy, Honoraria; Celgene: Consultancy, Honoraria, Research Funding. Scheid:Ortho Biotech: Honoraria. Velde:Johnson & Johnson: Employment. Schmidt-Wolf:Janssen Cilag: financial support (symposium); Celgene: Membership on an entity's Board of Directors or advisory committees. Sonneveld:Johnson & Johnson: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees; Millenium: Membership on an entity's Board of Directors or advisory committees.


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 351-351 ◽  
Author(s):  
Paola Guglielmelli ◽  
Giada Rotunno ◽  
Annalisa Pacilli ◽  
Elisa Rumi ◽  
Vittorio Rosti ◽  
...  

Abstract Background. The prognostic significance of bone marrow (BM) fibrosis grade in pts with primary myelofibrosis (PMF) is debated. A fibrosis grade greater than 1 was associated with a 2-fold higher risk of death compared with pts with early/prefibrotic MF (grade 0) [Thiele J, Ann Hematol 2006]. Recent data suggest that more accurate prediction of survival is achieved when fibrosis grade is added to IPSS [Verner C, Blood 2008; Giannelli U, Mod Pathol 2012]. Aim. To analyze the prognostic impact of fibrosis in diagnostic BM samples of 540 WHO-2008 diagnosed PMF pts with extensive clinical and molecular information collected in 6 Italian centers belonging to AGIMM (AIRC-Gruppo Italiano Malattie Mieloproliferative). Methods. The clinical variables assessed were those previously identified as prognostically relevant in the IPSS score. Published methods were used to screen mutations of JAK2, MPL, CALR, EZH2, ASXL1, IDH1/2 and SRSF2. European consensus scoring system was used to grade fibrosis (on a scale of MF-0 to MF-3). The prognostic value of fibrosis with regard to overall survival (OS) was estimated by Kaplan-Meier method and Cox regression. Results. Pts' median age was 61y; median follow-up 3.7y; median OS 10.5y; 184 pts (34.1%) died. IPSS risk category: low 33.7%, Int-1 27.7%, Int-2 19.1%, High-risk 19.5%. Mutational rate: JAK2 V617F 62.6%, CALR 20.7% (type-1/1-like 77.7%, type2/2-like-2 21.4%), MPL W515 5.9%; 62 (11.5%) were triple negative (TN). 171 pts (31.7%) were High-Molecular Risk (HMR) category (Vannucchi AM, Leukemia 2013); mutation rate: EZH2 7.2%, ASXL1 22.2%, IDH1-2 2.4%, SRSF2 8.3%. According to fibrosis grading, 50 pts were MF-0 (9.3%), 180 MF-1 (33.3%), 196 MF-2 (36.3%), 114 MF-3 (21.1%). Compared with both MF-0 and MF-1, MF-2 and MF-3 pts presented more frequently constitutional symptoms (P<.0001), larger splenomegaly (P<.0001), greater risk of developing anemia (P<.0001) or thrombocytopenia (P=.003). We found a significant association (P<.0001) between IPSS higher/Int-2 risk categories and MF-2 and -3 (20.5% and 37.8%, respectively, vs 14.8% and 6.0% for MF-0 and -1). There was no correlation between fibrosis grade and phenotypic driver mutations; in particular, TN pts were equally distributed among MF fibrosis grades (10%, 10.6%, 14.3% and 8.8% from MF-0 to -3, respectively). Conversely, the frequency of HMR pts increased progressively according to fibrosis grade: 8 pts MF-0 (16%), 46 MF-1 (25.6%), 66 MF-2 (33.7%) and 51 MF-3 (44.7%) (P<.0001). In particular, we found a significant association between fibrosis grade and ASXL1 (12%, 15%, 23.5% and 36% from MF-0 to -3; P<.0001) and EZH2 (2%, 3.9%, 8.2%, 13.2%; P=.01) mutations. Also, pts with 2 or more HMR mutated genes were preferentially MF-2 or -3 ( 0%, 4.4% 10.2% and 10.5% from MF-0 to -3; P=.001). Median OS was significantly shorter in pts with MF-2 (OS 6.7y, HR 7.3, IC95% 2.7-20.0; P<.0001) and MF-3 (OS 7.2y, HR 8.7, IC95% 3.1-24.2; P<.0001) compared with MF-1 (14.7y; HR 3.9, IC95% 1.4-10.9, P=.008) and MF-0 (P<.0001) used as reference group (OS not reached) (Figure). Excluding MF-0, MF-2 and -3 maintained negative prognostic impact with HR 1.9 (1.3-2.6; P=.001) and 2.2 (1.5-3.3; P<.0001) respectively vs MF-1. The impact of fibrosis on OS was maintained when analysis was restricted to younger (≤65y) pts. In multivariate analysis using the individual IPSS variables, grade MF-2 and -3 were independently predictive of survival (HR 3.9 (1.4-10.8), and HR 4.2 (1.5-12.0), respectively, P=.008 for both). The negative impact on survival of MF-2/-3 was maintained regardless of IPSS category, HMR status, number of HMR mutated genes and driver mutations, included as covariates (Table). In low, Int-1 and Int-2, but not high-risk IPSS categories, MF-2/-3 associated with reduced survival (P<.03). Conclusions. Overall, these results indicate that higher grades (MF-2 and MF-3) of fibrosis correlate with defined clinical and molecular variables and independently negatively impact on OS in PMF, suggesting the opportunity to explore its value in the setting of clinical and molecular prognostic scores for PMF. Table. Multivariate Analysis Variables HR 95% CI P value HMR status 2.4 1.5-3.7 <.0001 HMR≥2mutations 4.3 2.8-6.4 .009 IPSS scoring Int1 2.9 1.6-5.1 <.0001 Int2 10.0 5.6-17.7 <.0001 High 9.7 5.5-17.2 <.0001 Driver mutations CALR type2 3.4 1.3-8.6 .010 JAK2/MPL 2.4 1.4-4.3 .003 TN 4.5 2.3-8.8 <.0001 Fibrosis MF-2/MF-3 3.8 1.4-10.6 .010 Figure 1. Figure 1. Disclosures Passamonti: Novartis: Consultancy, Honoraria, Speakers Bureau. Barbui:Novartis: Speakers Bureau. Vannucchi:Shire: Speakers Bureau; Novartis: Other: Research Funding paid to institution (University of Florence), Research Funding; Baxalta: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau.


Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 4635-4635
Author(s):  
Vera Adema ◽  
Laura Palomo ◽  
María Díez-Campelo ◽  
Mar Mallo ◽  
Leonor Arenillas ◽  
...  

Abstract INTRODUCTION Myelodysplastic syndromes (MDS) are a heterogeneous group of clonal myeloid stem cell disorders that are highly prevalent in elderly populations. MDS are characterized by inefficient hematopoiesis, peripheral blood (PB) cytopenias, and increased risk of transformation to acute myeloid leukemia (AML; 20–30% of patients with MDS). Around 50% of MDS patients carry at least one karyotypic aberration. The interstitial deletion of the long arm of chromosome 5 ([del(5q)] is the most common aberration, accounting for almost 30% of abnormal MDS karyotype. Various studies supports a favorable prognosis of MDS with isolated del(5q) with an excellent response to lenalidomide treatment. In order to describe the molecular events associated with MDS and del(5q) we performed whole-exome sequencing (WES)(assessing 334,378 exons) of tumor-normal paired samples from 20 MDS patients to unravel the genetic basis of MDS with del(5q). The analysis is ongoing and the complete results will be presented in the meeting. METHODS A total of 50 samples from 20 patients with MDS, with del(5q) were collected. For each diagnostic sample, we performed Conventional G-banding cytogenetics and fluorescence in situ hybridization (FISH, to confirm or dismiss del(5q)) and SNP arrays with Cytoscan HD (Affymetrix). These samples included: 20 tumor samples at diagnosis, 20 control samples and 10 samples after diagnosis, during lenalidomide treatment (5) or at the moment of relapse (5) in order to compare the genetic status before and during the treatment. Genomic DNA from tumor cells was obtained from bone marrow (BM) samples or from PB granulocytes. As a source of constitutional DNA we used CD3+T cells from each patient by isolating by magnetic-activated cell sorting. WES targeted capture was carried out on 7μg of genomic DNA, using the SureSelect Human Exome Kit 51Mb version 4.Libraries were sequenced on an Illumina HiSeq2000. Sequencing data will be analyzed using an in-house bioinformatics pipeline as previously reported. RESULTS Our preliminary analysis of these 20 new patients by WES confirmed our previous analyses with mutations in well described genes as ASXL1, JAK2 and TET2, but not in genes RUNX1, SF3B1 and SRSF2. In those patients we found two patients with missense mutation in TP53, one of the patients had an isolated del(5q) and is receiving lenalidomide treatment, and the other one had a complex karyotype. According to our prior analyses, in which 249 non-silent somatic variants were detected, we look forward to validate these mutations in this new series of patients. CONCLUSIONS We envision to validate these previous results with the new sequencing data of more patients with MDS and del(5q). We expect to measure somatic mutations that vary in abundance after lenalidomide treatment, potentially identifying mutations associated with resistance or relapse. ACKNOWLEDGEMENTS: This work has been supported (in part) by a grants from Instituto de Salud Carlos III, Ministerio de Sanidad y Consumo, Spain (PI 11/02010); by Red Temática de Investigación Cooperativa en Cáncer (RTICC, FEDER) (RD07/0020/2004; RD12/0036/0044); 2014 SGR225 (GRE) Generalitat de Catalunya; Fundació Internacional Josep Carreras; Obra Social “la Caixa”; Sociedad Española de Hematología y Hemoterapia (SEHH)and Celgene Spain. FOOTNOTES Rafael Bejar and Francesc Sole contributed equally. Disclosures Díez-Campelo: Novartis, Celgene: Honoraria, Research Funding. Xicoy:Celgene: Honoraria. Cañizo:Celgene, Jansen-Cilag, Arry, Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. sanchez-Garcia:Celgene: Honoraria, Research Funding. Bejar:Celgene: Membership on an entity's Board of Directors or advisory committees; Genoptix Medical Laboratory: Consultancy, Honoraria, Licensed IP, no royalties Patents & Royalties, Membership on an entity's Board of Directors or advisory committees. Sole:Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding.


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