Adult Acute Myeloid Leukemia Pts Research Articles

The Ancestry-Related Landscape of Long Non-Coding RNAs (LncRNAs) in Acute Myeloid Leukemia (AML) and Its Impact on Patient (Pt) Survival

Background In addition to molecular genetic and cytogenetic findings, gene expression profiles provide independent prognostic information in AML. Aberrant expression of non-coding RNAs, including lncRNAs, further inform pt prognosis. However, non-coding expression profiles and their clinical relevance in AML almost exclusively stem from studies of pts of European ancestry (hereafter referred to as White). Given the inferior survival of African-American (hereafter referred to as Black) AML pts, we hypothesized that aberrant, possibly ancestry-associated lncRNA expression may contribute to survival disparities. Hence, we set out to (1) characterize the lncRNA landscape of African-American ancestry, (2) delineate associations of lncRNAs with clinical and molecular characteristics and (3) assess the prognostic significance of ancestry-associated lncRNAs in AML. Methods We used diagnostic samples from 681 adult AML pts (<60y) treated similarly on Alliance frontline protocols (White, n=616; Black, n=65) for RNAseq, mutational profiling and centrally reviewed karyotyping. A negative binomial model was fit to identify lncRNAs differentially expressed between Black and White pts. To determine prognostic relevance of identified lncRNAs, 10-fold cross-validation repeated 1000 times was performed on LASSO penalized Cox proportional hazards model to overall survival (OS). LncRNAs appearing in at least 900 of the 1000 models were retained and coefficient estimates were averaged then applied to form the “lncRNA score.” Ancestry-associated SNPs in regulatory regions of select lncRNAs were identified using the ENCODE registry for cCREs, SNP2TFBS and population allele frequency data from NCBI ALFA. Results Comparing Black and White AML pts, 135 lncRNAs were upregulated and 55 lncRNAs were downregulated. The differentially expressed lncRNAs were equally distributed throughout the genome and no lncRNA was ancestry-exclusive in its expression, indicating high conservation. lncRNAs with the highest differential expression include several lncRNAs previously implicated in cancer/leukemia, but also thus far unstudied lncRNAs. Using the 190 aberrantly expressed lncRNAs identified from comparison of Black and White pts, we derived a prognostic score (lncRNA score) consisting of 13 lncRNAs. LncRNA High strongly associated with inferior OS in all pts ( Fig. 1). In all pts combined, presence of lncRNA High positively associated with several adverse-risk features, and negatively associated with core-binding factor AML and CEBPA bZIP mutations. Notably, select genetic features differed in their lncRNA score associations based on ancestry, including a relative paucity of cytogenetically normal AML (29% vs 57%), NPM1 (13% vs 40%) and CEBPA bZIP (8% vs 17.5%) mutations in Black pts compared to White pts in the lncRNA Low group. lncRNA score was an independent prognosticator of worse OS in both Black and White pts that refined the prognostication of the European LeukemiaNet 2022 Favorable (P=.004) and Intermediate (P<.001) genetic risk groups. It also provided further prognostic information to the LSC17 score in both low (P<.001) and high (P<.001) LSC17 groups. Examination of the genomic context of regulatory regions within the 13 lncRNAs revealed multiple ancestry-associated SNPs that putatively altered transcription factor / chromatin regulator binding sites in cis-regulatory regions, including rs58515841 (MAF White vs Black, 24% vs 9%, CTCF binding site within ENSG00000284052) and rs1400262 (MAF, 62% vs 10%, REST binding site upstream of NCK1-DT). Conclusions We show an ancestry-related landscape of lncRNAs in AML, including an ancestry-associated expression profile of lncRNAs and evidence of ancestry-associated SNPs as expression modulators. A prognosis-associated lncRNA score based on differentially expressed lncRNAs in Black versus White AML pts carries prognostic significance irrespective of ancestry and refines both mutation/cytogenetically-based (ELN 2022) and gene-expression-based (LSC17) prognostic algorithms. Our findings highlight the importance of ancestry-diverse populations in the establishment of prognostic scoring systems to provide ancestry-connected survival prediction. Support: U10CA180821, U10CA180882, U24CA196171; https://acknowledgments.alliancefound.org. Clinicaltrials.gov Ids: NCT00048958, NCT00899223, NCT00900224

Ubtf- Tandem Duplications Are Recurrent Somatic Genetic Events in Adult AML and Associate with Additional Structural Variants and a Distinct Gene Expression Profile (Alliance)

Background The gene upstream binding transcription factor ( UBTF ) encodesa nucleolar protein that is a key regulator of the epigenetic status of ribosomal DNA and RNA transcription. Tandem duplications (TDs) of the UBTF gene have been initially identified in pediatric patients (pts) with acute myeloid leukemia (AML) and were recently also reported as relatively rare, but recurrent genetic events in adult AML based on targeted re-sequencing efforts (1.2%-3%). Their presence was associated with dysplastic bone marrow features, and co-occurrence of select genetic features, including FLT3-internal tandem duplications (ITDs) and WT1 mutations, and inferior outcome. However, associated biologic features and affected pathways have not yet been thoroughly investigated, and may provide further insights into leukemogenesis and identify potentially targetable vulnerabilities. Thus, we set out to assess the frequency of UBTF-TDs in a large cohort of adult AML pts (n=807) treated on frontline protocols of the Alliance for Clinical Trials in Oncology with complete RNA sequencing data, comprehensive targeted mutation profiling, centrally reviewed cytogenetic data and clinical information available, and to gain further insights into UBTF-TDs via comprehensive integrated genomic profiling. Methods UBTF-TD detection was performed via the RNAseq-based RNAmut and EnFusion algorithm. To gain insights into associated molecular features, all UBTF-TD + pts underwent paired tumor-normal whole-exome sequencing. To understand associated pathways and downstream effects, differential gene expression (DGE) and gene set enrichment analyses (GSEA) were performed. Results UBTF-TDs were detected in 6/807 pts (0.7%). In line with previous studies, these 6 UBTF-TD + pts were young, with a median age of 35y (range: 19-59y). Three pts had extramedullary disease, 2 with skin and 1 with gingival involvement. All but 1 of the 6 pts were cytogenetically normal. Clinically, pts did poorly after treatment with intensive chemotherapy induction, with a CR rate of only 33%. No pt was alive 2.5 y after diagnosis. In paired tumor/normal exome sequencing, UBTF-TD + pts had a median mutation burden of 21 non-synonymous variants in coding genes (range: 17-27), with a notable presence of larger insertions/deletions (indels), loss of heterozygosity (LOH) or TDs as co-occurring somatic genetic lesions (median: 4, range: 2-5). There was a 100% co-occurrence of UBTF-TDs with FLT3-ITDs. In addition, pts harbored larger indels in WT1 (n=2), BPTF, CEBPA, Corf53, KRTAP5-7, NFE2, PTPRN2, RNF144B, SOWAHC and ZCCHC14. Also, analysis of copy-number variations and LOH revealed LOH in 5 pts, in chromosomes 13 (n=3), 15 (n=1) and 18 (n=1), suggestive of a propensity to the acquisition of structural variants. In unsupervised clustering analysis of the RNAseq data, UBTF-TD + pts clustered with FLT3-ITD + pts but formed a relatively distinct subcluster in principal component and t-distributed stochastic neighbor embedding analyses. In supervised clustering comparing 6 UBTF-TD +/ FLT3-ITD + and 196 UBTF-TD -/ FLT3-ITD + pts, 2 UBTF-TD - pts clustered together with the UBTF-TD +/ FLT3-ITD + group, suggesting either presence of an undetected TD or genetic phenocopy. UBTF expression was higher in UBTF-TD pts. DGE analysis of UBTF-TD +/ FLT3-ITD + and UBTF-TD -/ FLT3-ITD + pts (Fig 1) showed distinct upregulation of the locus of the stem cell and chemoresistance marker ALDH1A3, including the associated long non-coding RNAs AC015712.7/AC015712.2 in UBTF-TD + pts, which was confirmed by a comparison of those pts to AML pts who had neither TD (n=605). GSEA indicated a downregulation of inflammation pathways and several metabolic pathways of UBTF-TD +/ FLT3-ITD + compared to FLT3-ITD + pts (Fig 2). Conclusions UBTF-TDs are rare, but recurrent genetic events in adult AML, associated with high chemotherapy resistance. Our results highlight a susceptibility of those pts to the acquisition of structural variants and suggest a distinct associated biology, with upregulation of ALDH1A3 as possible contributing resistance mechanism. Support: U10CA180821, U10CA180882, U24CA196171; Clinicaltrials.gov Identifiers: NCT00048958 (CALGB 8461), NCT00899223 (CALGB 9665), NCT00900224 (CALGB 20202); https://acknowledgments.alliancefound.org

Molecular Landscape in Acute Myeloid Leukemia (AML) Patients (pts) from Mexico As an Initial Study to Identify Healthcare Disparities in Hispanic Populations: Alliance for Clinical Trials in Oncology [Alliance

Health care disparities are associated with social, economic and environmental disadvantages and may adversely affect minority groups. "Hispanic or Latino” refers to a person of Cuban, Mexican, Puerto Rican, South or Central American, or other Spanish origin or culture regardless of race. To begin to understand disparities in Hispanic pts with AML, we thought to characterize and compare clinical features, mutationallandscape and disease outcomes of AML pts from Mexico and Hispanic (Hisp) AML pts living in the US and compare them with those of non-Hispanic White (NHW) pts. Methods: We assessed molecular features and outcomes of 48 adult AML pts diagnosed and treated with anthracycline and cytarabine combination (90%) at the Hospital General De Mexico (HGM, a urban public tertiary hospital and a referral institution for AML pts in Mexico City) (cohort 1: Mex), as well as 48 adult AML pts who self-identified as Hispanic and 1496 non-Hispanic White pts similarly treated on frontline Alliance protocols (cohort 2: A-Hisp, A-NHW). No pt received an allogeneic transplant in 1st complete remission. Mutational status of 55 protein-coding genes in addition to the main fusion gene rearrangements at time of diagnosis were determined by both study groups centrally using targeted NGS platforms. Last, we used 2 additional reported Hispanic cohorts in the US and large international cohorts for validation of the identified molecular and clinical features (cohort 3 [] and 4). Results: Median age at diagnosis for cohorts 1 and 2 was younger than reported for AML, 38yo (15-86) for cohort 1 vs 45yo (17-83) for cohort 2. Somatic mutations in the cohort 1 were detected in 96% of pts, similar to the A-Hisp subset of cohort 2 (94%). The most prevalent mutations in the cohorts were FLT3 (Mex 29%, A-Hisp 33%, A-NHW 42%, p= 0.654), followed by CEBPA (Mex 21%, A-Hisp 15%, A-NHW 13%, p=0.214), TET2(Mex 19%, A-Hisp 8%, A-NHW 16%, p=0.322), DNMT3A (Mex 19%, A-Hisp 18%, A-NHW 24%, p=0.5498), RUNX1 (Mex 15%, A-Hisp 0%, A-NHW 12%, p<0.001) and NPM1 (Mex 12%, A-Hisp 29%, A-NHW 35%, p=0.002). Fusion genes were detected in 21% of pts, with t(8;21)(RUNX1-RUNX1T1) being the most commonly found (Mex 13%, A-Hisp 6%, A-NHW 3%, p=0.005), followed by MLL rearrangements (Mex 4%, A-Hisp 16%, A-NHW 5%, p=0.015) and inv(16)(CBFB-MYH11) (Mex 2%, A-Hisp 10%, A-NHW 2%, p=0.003). We found some commonalities in the genetic alterations between these two Hispanic cohorts (i.e., CEBPA, FLT3, DNMT3A), however median overall survival (OS) for the Mexican cohort was 9mo, worse than OS for cohort 2 (A-Hisp 15mo, A-NHW 14mo). Those molecular differences were validated in 2 additional international cohorts (TCGA and Pappaemmanuil et al., NEJM, 2016). Notably, there was an overrepresentation of CEBPA mutated AML in both cohort 1 and A-Hisp (cohort 2). The most notable difference between the two Hispanic cohorts (Mex vs A-Hisp) was the prevalence of mutated NPM1, which was higher in the US A-Hisp dataset, similar to what is described in other international cohorts for de novo AML. Conclusion: Mexican AML pts have a distinct genetic makeup and overall poorer outcomes compared to other international cohorts. These differences in genetic alterations point to differences in host genetic susceptibility and environmental factors. Because the term Hispanic reflects a culture rather than a genetically defined ethnicity we will perform ancestry-specific analysis to better characterize the genetic differences and determine who is represented within this heterogeneous population, particularly in the self-reported population living in the US. Some of the detected variants are targetable mutations that could influence disease management decisions. It is important to use ancestry-specific analysis, as compared with self-reported race and ethnicity, to better understand the impact on disparities and highlighting the importance of increasing enrollment of Hispanic pts in clinical trials. Knowing who is accessing healthcare in the US as self-reported Hispanic will help understand whether the differences in outcome are related to healthcare access or there is a genetic component that could explain some of the differences in age of onset and molecular findings observed in cohorts of similar ethnic background.

Prognostic Impact of Monoallelic Versus Biallelic TP53 Alterations in Intensively-Treated Adults AML Patients: A Retrospective Study from the ALFA Group

Introduction:TP53 is a key tumor suppressor gene involved in apoptotic pathways, metabolism functions, preservation of genomic balance and DNA repairs. TP53 locus is subject to mutations, deletions and copy-neural loss of heterozygosity. TP53 mutations are associated with a reduced overall survival and are assigned to the ELN 2017 adverse-risk group. Recent studies have suggested a worse prognostic impact of biallelic TP53 alterations compared to monoallelic TP53 mutations in myelodysplastic syndromes (Bernard et al, Nat. Medicine, 2020). Whether TP53 allelic state impairs the prognostic in intensively-treated acute myeloid leukemia (AML) patients and may refine the treatment strategy has not been addressed. Here, we analysed TP53 alterations in newly diagnosed AML patients (pts) from 3 prospective Acute Leukemia French Association (ALFA) trials. Methods: A total of 983 adult AML pts enrolled in ALFA-0701 (NCT00927498), ALFA-0702 (NCT00932412) and ALFA-1200 (NCT01966497) trials were retrospectively screened for TP53 alterations by high throughput sequencing and conventional cytogenetics. Pts displaying at least two TP53 mutations or one TP53 mutation associated with either TP53 locus deletion or TP53 locus copy-neutral loss of heterozygosity (CN-LOH) were assigned as biallelic TP53 alteration patients. TP53 locus CN-LOH were approximated based on variant allele frequencies and copy number analysis. Survival was analysed with multivariate Cox models stratified on the trial. Results: Eighty-three patients had TP53 mutations (8%; ALFA-0701: n=21, ALFA-0702: n=28; ALFA-1200: n=34), including 14 pts with monoallelic and 69 pts with biallelic TP53 alterations respectively. Median age of TP53 mutated patients was 62 years (IQR: 57-68). Leukocytes counts and bone marrow blast counts at diagnosis were lower in TP53 mutated patients (3.0 G/L vs. 8.7 G/L, p<0.0001; 40% vs. 58%, p=0.002, respectively). Median variant allele frequency of TP53 mutations was 43% (IQR: 21-69). As compared to TP53 wildtype AML, TP53 mutated pts more often harbored complex karyotype (n=69 (86%) vs n=51 (6%), p<0.0001) and monosomal karyotype (n=65 (81%) vs n=32 (4%), p<0.0001). The median number of additional mutations was 2 (IQR: 0-3). TP53 mutations were associated with mutations in signalling genes (NF1, NRAS, PTPN11, KRAS, FLT3, KIT and JAK2) in 33 pts (40%). Overall, 43 TP53 mutated AML patients (52%) achieved complete remission (CR)/complete remission without platelet recovery (CRp) after one or two courses of induction whereas 684 TP53-wt patients (76%) were in CR/CRp at that time (p<0.0001). TP53 mutations were associated with a significantly reduced OS and DFS in multivariate analysis including age and WBC count (2-year OS, 11% vs 56%, HR: 3.48, 95% CI: 2.71-4.47, p<0.0001; 2-year DFS, 12% vs 50%, HR: 2.97, 95% CI: 2.12-4.16, p<0.0001, respectively). Among TP53 mutated AML, biallelic TP53 alterations were associated with worse OS compared to monoallelic TP53 alterations (2-year OS, 4% vs 43%, HR: 4.13, 95% CI: 1.87-9.13, p=0.0004 in multivariate analysis accounting for age and WBC count). Interestingly, outcome of the 2017 ELN risk stratification intermediate group was not different to that of monoallelic TP53 pts (2-year OS, 43% for monoallelic TP53 pts vs 53%, HR: 1.07, 95% CI: 0.55-2.07, p=0.84). In pts with biallelic TP53 alterations, presence of signalling mutations was associated with a worse survival in a multivariate analysis accounting for age and WBC (HR: 1.82, 95% CI: 1.06-3.11, p=0.03). Conclusion: Allelic status refines the prognostic value of TP53 mutations in AML. While monoallelic TP53 alterations display similar outcome to that of the ELN 2017 intermediate risk group, biallelic TP53 alterations dramatically impair patient outcome. Patients with biallelic TP53 alterations may be good candidates for new first-line treatment strategies. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Comparative Outcomes and Molecular Response Predictors of IDH1/2-Mutated Adult Acute Myeloid Leukemia (AML) Patients (Pts) after Frontline Treatment with Intensive Induction Chemotherapy (IC), Targeted Inhibitors, or Hypomethylating Agents (HMA) (Alliance)

Comparative Outcomes and Molecular Response Predictors of IDH1/2-Mutated Adult Acute Myeloid Leukemia (AML) Patients (Pts) after Frontline Treatment with Intensive Induction Chemotherapy (IC), Targeted Inhibitors, or Hypomethylating Agents (HMA) (Alliance)

Multi-Dimensional Analysis of Adult Acute Myeloid Leukemia (AML) Landscape Cross-Continents Reveals Age Associated Trends in Mutations and Outcomes

Multi-Dimensional Analysis of Adult Acute Myeloid Leukemia (AML) Landscape Cross-Continents Reveals Age Associated Trends in Mutations and Outcomes

Acute Myeloid Leukemia (AML) Patients with an Isolated Trisomy Display Increased Frequency of Spliceosome Mutations

Abstract Introduction: The molecular landscape of patients (pts) with cytogenetically normal (CN) AML has been extensively evaluated; however, there are limited data providing comprehensive mutation analysis of AML pts with sole somatic trisomy. A few analyses with small numbers of pts found frequent mutations of spliceosome encoding genes (Eisfeld et al, Leukemia 2016, Herold et al, Blood 2014). Methods: Review of the Cancer and Leukemia Group B/Alliance for Clinical Trials in Oncology cytogenetics database found 138 de novo adult AML pts with isolated trisomy of chromosomes 4, 8, 11, 13 or 21. We compared clinical and molecular data between pts within each isolated trisomy group as well as with 131 pts who had ≥1 chromosome abnormality in addition to a trisomy (non-sole trisomy) and with 716 pts with CN-AML. Results: Spliceosome encoding genes, mainly SRSF2 and U2AF1, were often mutated in pts with isolated trisomy (Figure 1). SRSF2 was mutated in 28% of +8 pts and 35% of +21 pts. SRSF2 mutations were the most common mutation in +13 pts, seen in 48% of +13 pts. U2AF1 was mutated in 15% of +8 pts and in 43% of +11 pts. Other genes commonly mutated in each trisomy group included DNMT3A, FLT3 -ITD, IDH2, NRAS, RUNX1 and TET2. Notably, pts with +4 lacked mutations in ASXL1, BCOR, STAG2 and WT1 genes, all of which were mutated in pts in the other sole trisomy groups. NPM1 mutations, often seen in the +4, +8, +13 and +21 groups, were not seen in +11 pts. There were no differences in complete remission rates, relapse rates, disease-free or overall survival among trisomy groups. For pre-treatment clinical features of the 138 de novo isolated trisomy AML pts see Table 1. The median age was 61 years (range, 19-84 years). We saw several differences in the mutation spectrum between older (aged ≥60 years) and younger (aged We next studied molecular differences between the 138 sole trisomy pts and 131 pts with non-sole trisomy. We saw more mutations in SRSF2 (29% vs 14%, P=.003) and U2AF1 (14% vs 14%, P=.003) in sole trisomy versus non-sole trisomy pts. Several genes were often mutated (≥5%) in both sole and non-sole trisomy groups; most common were spliceosome genes SRSF2 , U2AF1, ZRSR2, and others were ASXL1, BCOR, DNMT3A, FLT3 -ITD, FLT3 -TKD, IDH1, IDH2, NPM1, NRAS, RUNX1, STAG2, TET2. TP53 mutations were often seen in non-sole trisomy pts, but were rare in sole trisomy pts (17% vs 1%, P Comparing sole trisomy pts to 716 CN-AML pts, we found spliceosome encoding genes more often mutated (48% vs 19%, P Conclusions: This is the largest series of de novo AML pts with isolated trisomy that provides comprehensive mutation analysis. These pts display a distinct molecular landscape from AML pts with non-sole trisomy and from CN-AML pts. Mutations affecting spliceosome encoding genes were seen in almost 50% of pts with isolated trisomy suggesting that aberrant RNA splicing may be implicated in the pathogenesis of these pts. Support: U10CA180821, U10CA180850, U10CA180882, U24CA196171; ClinicalTrials.gov Ids: NCT00048958, NCT00900224 Download : Download high-res image (236KB) Download : Download full-size image Disclosures Kolitz: Gilead, Magellan, Novartis, Pharmacyclics, and Seattle Genetics: Consultancy; Boehringer Ingelheim, Cantex, Erytech, and Millennium: Research Funding; Gilead, Novartis, and Seattle Genetics: Other: Travel Support; Celgene, Jazz: Equity Ownership; Gilead, Magellan, and Novartis: Honoraria. Powell: Rafael Pharmaceuticals: Consultancy, Membership on an entity's Board of Directors or advisory committees. Byrd: Acerta Pharma: Research Funding; Genentech: Research Funding; The Ohio State University: Patents & Royalties: OSU-2S; Janssen: Research Funding; Pharmacyclics: Research Funding.

Risk Factors Associated with 30-Day Unplanned Readmissions for Adult Acute Myeloid Leukemia (AML)

Risk Factors Associated with 30-Day Unplanned Readmissions for Adult Acute Myeloid Leukemia (AML)

Poor Treatment Outcomes of Young (

Poor Treatment Outcomes of Young (<60 Years) African American Patients (Pts) Diagnosed with Acute Myeloid Leukemia (AML) (Alliance)

Clinical and Prognostic Implications of PTPN11 Mutations in Acute Myeloid Leukemia (Alliance)

Clinical and Prognostic Implications of PTPN11 Mutations in Acute Myeloid Leukemia (Alliance)

Filgrastim Administered after Early Assessment Bone Marrow Biopsy during 7+3 Induction Therapy for Acute Myeloid Leukemia Reduces Length of Hospital Stay

Background National guidelines for acute myeloid leukemia (AML) therapy do not routinely recommend granulocyte colony stimulating factors (GCSF) during intensive induction therapy. Randomized trials have showed GCSF administration immediately after induction chemotherapy does improve time to absolute neutrophil count (ANC) recovery but is not associated with either improvements nor detriments to disease progression and survival. There are also concerns that GCSF may affect interpretation of bone marrow biopsy (BmBx) results. At the Seidman Cancer Center, GCSF has frequently been initiated AML patients (pts) undergoing induction chemotherapy after confirmation of hypoplasia in a day 14 BmBx (D14BM). Few studies have examined the potential role of GCSF initiated after confirmation of hypoplasia on D14BM. We hypothesized that this selective use of GCSF in (pts) with hypoplastic D14BM could improve short term outcomes from induction therapy. Methods Newly diagnosed adult AML pts receiving first-line inpatient induction therapy from 2003 through 2019 were retrospectively evaluated at the Seidman Cancer Center. Patients were included met criteria for hypoplasia on D14BM. Patients were stratified on whether they initiated GCSF within 5 days of the D14BM. Outcomes of interest included time from treatment start to discharge, number of febrile days, time to absolute neutrophil count (ANC) recovery to 1Î109 cells/L, effects on BmBx after count recovery, progression free survival (PFS) and overall survival (OS). Results We identified 121 patients meeting inclusion criteria. Patient characteristics are listed in Table 1. Patients receiving GCSF after D14BM were slightly more likely to be female, but overall groups were well balanced for age, race, performance status (PS), European Leukemia Net 2017 disease risk, baseline marrow blasts percentage and WBC, time from diagnostic biopsy to treatment, and specific induction regimen received. Within the GCSF after D14BM group, GCSF was started a median of 2 days (range 0-5) after D14BM. A median of 6 days of GCSF was administered in the intervention group. Patients receiving GCSF had inpatient hospital stay of 24 (95% CI 24-26) days versus 26 (95% CI 25-27) days (p = 0.0039) for those without GCSF after the start of induction therapy. Days to ANC recovery from start of induction was decreased in in the early GCSF group 23 (95% CI 22-24) vs 25 (95% CI 24-27) days (p = 0.008). There was no effect on platelet recovery, with a median of 23 versus 24 days, p = 0.53. Cox proportional hazard models were used to assess for impact of age, PS, Race, ELN risk, time to threat start, diagnostic marrow blasts percentage and WBC at time of treatment start. Only early GCSF remained significantly associated with time to discharge (Hazard ratio for discharge 1.70, 95% CI 1.02 to 2.82) or ANC recovery (Hazard ratio for ANC recovery 1.95, 95% CI 1.16 to 3.26). GCSF after D14BM was not associated with a reduction in febrile days (mean of 4.2 versus 3.3, p = 0.16). Subsequent BmBx to assess response did not have significantly increase marrow blasts for patients receiving GCSF after D14BM (mean 7.6% versus 1.4%, p = 0.08) nor was it associated with increased risk of refractory disease (Odds Ratio 1.4, 95% CI 0.46 to 4.46). Finally, early GCSF after D14BM did not result in significant changes in PFS (median 8.8 years versus 4.8 years, p = 0.24) or OS (median 9.1 years vs 4.8 years, p = 0.38). Conclusion For AML patients who achieve hypoplasia on D14BM during induction, GCSF administered after early assessment biopsy is associated with reduced time to ANC recovery and inpatient time. Interpretation of response marrows did not appear to be affected. Disclosures Caimi: Genentech: Research Funding; ADC Therapeutics: Research Funding; Celgene: Speakers Bureau. Malek:Janssen: Speakers Bureau; Medpacto: Research Funding; Sanofi: Consultancy; Takeda: Consultancy; Celgene: Consultancy; Amgen: Speakers Bureau; Adaptive: Consultancy. Metheny:Takeda: Speakers Bureau; Incyte: Speakers Bureau.

ASXL1/SRSF2 Co-Mutated Acute Myeloid Leukemia (AML): A Rare but Distinct Subpopulation with Dismal Outcomes

Background: Advances in the understanding of the genetic determinants of AML and the widespread use of next-generation sequencing (NGS) have led to the refinement of prognostically distinct molecular subgroups. Mutations in ASXL1 and SRSF2, which are common in myelodysplastic syndrome (MDS) and myeloproliferative neoplasms (MPNs), rarely co-occur in patients (pts) with AML. The largest reported cohort (n=15) of ASXL1/SRSF2 co-mutated AML had no long-term survivors (Papaemmanuil et al. NEJM 2016). It remains unknown how clinical factors such as prior history of a myeloid neoplasm or intensity of treatment influence outcomes. We sought to assess the clinical characteristics and analyze outcomes in a larger cohort of pts with ASXL1/SRSF2 co-mutated AML. We hypothesized that this profile may be a genomic footprint of prior myeloid neoplasia. Methods: We conducted a multi-institutional retrospective analysis of newly diagnosed adult AML pts with both ASXL1 and SRSF2 mutations at the University of North Carolina and at Moffitt Cancer Center from 2011-2018. NGS was performed on DNA using the Illumina TruSight Myeloid 54-gene sequencing panel. The primary endpoint was overall survival (OS) defined as time from diagnosis of AML to death. Pts were stratified by secondary AML (s-AML), defined as having a documented history of MDS/MPN. Secondary outcomes included rates of complete remission (CR) and CR with incomplete hematologic recovery (CRi). Multivariable analysis was performed with baseline characteristics. Results: Forty-six pts were identified and included. The median age of pts was 72 years (range 42 - 85). Sixty-seven percent (28/42) had normal cytogenetics; 88% (37/42) were intermediate risk cytogenetics by current ELN guidelines. Sixty-one percent (n=28) were classified as having s-AML. One pt had therapy-related AML without preexisting MDS/MPN and was therefore not included in s-AML. The Figure illustrates co-existing mutations and individual responses to upfront therapy stratified by s-AML and non-s-AML. The median number of mutations was 5 (range 2 - 7). The most common co-occurring mutations were TET2 (52%), RUNX1 (35%), IDH2 (15%), and STAG2 (15%). Median OS was 7.0 months (m) (CI 5.3, 15.4). Median OS for pts with s-AML (n=28) and non-s-AML (n=18) was 6.1 and 15.4 m (p=0.05), respectively. There was no significant difference in median OS between s-AML and non-s-AML on multivariable analysis (hazard ratio (HR) = 2.56, p=0.07). Median OS did not differ by age (Age &lt;65 years v. older, p=0.54), total # of mutations (≥ 5 v. less, p=0.73), or etiology of s-AML (MDS v. MPN, p=0.66). Twenty-two (47%) pts received upfront intensive induction chemotherapy (IC), 17 (37%) received hypomethylating agents (HMAs), and 7 pts (15%) received no AML-directed chemotherapy. Median OS did not significantly differ between pts receiving upfront IC and HMAs (15.3 v. 7.04 m, p=0.21). Among non-s-AML pts, median OS was longer in those receiving IC (n=10) versus HMAs (n=7) (15.4 v. 3.5 m, p=0.01). Among all pts receiving IC, median OS was longer in non-s-AML pts (n=10) versus s-AML pts (n=12) (15.4 v. 5.9 m, p=0.01). Median OS did not differ by treatment intensity for s-AML pts (IC v. HMA: 5.9 v. 9.9 m, p=0.38). Six pts underwent allogeneic hematopoietic cell transplant (HCT) with a median OS NR (median follow-up 15.6 m). Overall rate of CR/CRi was 35% and was similar between pts receiving IC and HMAs (45% v. 21%, p=0.29). Among pts with non-s-AML, CR/CRi rates with IC and HMAs were 70% and 29%, respectively (p=0.11). Among pts with s-AML, CR/CRi rates with IC and HMAs were 42% and 20%, respectively (p=0.38). On multivariable analysis of baseline characteristics, only ECOG performance status (PS) was significantly associated with OS (HR 2.25, p=0.01). ECOG PS remained significant (HR 2.65, p=0.03) after adjusting for HCT and treatment intensity. Conclusions: ASXL1/SRSF2 co-mutated AML represents a rare but distinct genotype with most pts having pre-existing myeloid neoplasms and associated co-mutations commonly seen in MDS/MPNs. OS is dismal regardless of age, number of mutations, treatment intensity, or prior history of myeloid neoplasm. HCT may mitigate these poor outcomes and lead to long-term survival. This represents the largest reported cohort to date of pts with ASXL1/SRSF2 co-mutated AML. Further study is warranted to inform risk stratification and prognosis of pts with ASXL1/SRSF2-mutated AML. Disclosures Foster: Bellicum Pharmaceuticals, Inc: Research Funding; Daiichi Sankyo: Consultancy; MacroGenics: Research Funding; Celgene: Research Funding. Coombs:Octopharma: Honoraria; Pharmacyclics: Honoraria; Medscape: Honoraria; Abbvie: Consultancy; Loxo: Honoraria; Cowen &amp; Co.: Consultancy; Dedham Group: Consultancy; H3 Biomedicine: Honoraria; Covance: Consultancy. Sallman:Celyad: Membership on an entity's Board of Directors or advisory committees. Zeidner:Agios: Honoraria; Celgene: Consultancy, Honoraria, Research Funding; Daiichi Sankyo: Honoraria; Tolero: Honoraria, Research Funding; Pfizer: Honoraria; AsystBio Laboratories: Consultancy; Merck: Research Funding; Takeda: Research Funding; AbbVie: Honoraria.

Identifying Factors That Predict for Unplanned Readmissions for Acute Myeloid Leukemia Patients Receiving Consolidation Cytarabine Based Therapies

Background: Younger patients (pts) with acute myeloid leukemia (AML) who enter a remission after intensive induction chemotherapy routinely receive at least one cycle of consolidation therapy with high dose cytarabine (HiDAC). This is commonly administered over a five-day inpatient stay, after which pts are discharged home as their blood counts nadir. It is thus a natural consequence of therapy that readmission for febrile neutropenia (FN) occurs, which can impact measures of quality and value in this population. Precise descriptions of incidence, type, and severity of infection, if identified, are lacking, and thus it is unknown to what standard cancer centers should be held for anticipated readmission. We measured these rates, and attempted to identify predictive factors for readmission. Methods: Adult AML pts ≥ 18 years of age who received at least one cycle of HiDAC consolidation (1000-3000 mg/m2 for six doses) in 2009-2019 were included. Our primary aim was to identify predictive factors for readmission after the first cycle of consolidation chemotherapy. The following pt characteristics and co-morbid conditions were analyzed: age, gender, body mass index (BMI), smoking status, AML cytogenetic risk status, history of diabetes, peripheral vascular disease, cardiovascular disease, chronic pulmonary disease, hepatic impairment, and other cancers. Secondary aims included: estimating rates of all-cause readmissions among all HiDAC cycles, defining the rate of FN readmissions, estimating rates of intensive care unit (ICU) admissions, clinical (e.g., probable pneumonia per imaging) and microbiologically-documented infections, prophylactic (ppx) medications used, and mortality. Statistical analyses interrogated potential risk factors for evidence of association with hospital readmission after the first cycle of consolidation chemotherapy. Results: We identified 182 AML pts who fit inclusion criteria. The median age was 50 years (range 19-73); 55% were female and 45% were male. Statistical analyses revealed no association with readmission after cycle 1 for cytogenetic risk (p=0.85), history of heart failure (p= 0.67), chronic pulmonary disease (p=1), connective tissue disease (p=0.53), cerebrovascular accident (p=0.63), diabetes (p=0.63), gender (p=0.07), history of lymphoma (p=0.53), other solid tumors (p=0.53), liver disease (p=1), myocardial infarction (p=0.71), peripheral vascular disease (p=1), or smoking status (p= 0.52). For 480 HiDAC cycles analyzed (88% at 3000 mg/m2), the overall readmission rate was 50% (242/480), of which 85% (205/242) were for FN. Those readmissions which were not FN were for cardiac complications (chest pain, EKG changes), non-neutropenic fevers or infections, neurotoxicity, bleeding or clotting events, or other symptoms associated with chemotherapy (nausea/vomiting, pain, etc.). Median time to FN hospital admission was 18 days (range 6-27) from the start of HiDAC. Of the 205 FN readmissions, 57% had documented infections. Of these infections, 41% were bacteremia, 23% fungal, 16% sepsis, 12% other bacterial, and 8% viral. Of 480 HiDAC cycles, ppx medications prescribed included: 92% fluoroquinolone (442/480), 81% anti-viral (389/480), 30 % anti-fungal (142/480), and 3% colony stimulating factor (14/480). Only 7% (14/205) of FN readmissions resulted in an ICU admission, and 1% (3/205) resulted in death. Conclusions: Approximately half of patients treated with consolidation therapy following intensive induction therapy can be expected to be readmitted to the hospital. The majority of FN readmissions were associated with clinical or microbiologically documented infections and are not avoidable, however ICU admission and death associated with these complications are rare. Readmission of AML pts following HiDAC is expected, and therefore, should be excluded from measures of value and quality. Disclosures Waldron: Amgen: Consultancy. Hobbs:Amgen: Research Funding; SimulStat Inc.: Consultancy. Advani:Macrogenics: Research Funding; Abbvie: Research Funding; Kite Pharmaceuticals: Consultancy; Pfizer: Honoraria, Research Funding; Amgen: Research Funding; Glycomimetics: Consultancy, Research Funding. Nazha:Incyte: Speakers Bureau; Abbvie: Consultancy; Daiichi Sankyo: Consultancy; Jazz Pharmacutical: Research Funding; Novartis: Speakers Bureau; MEI: Other: Data monitoring Committee; Tolero, Karyopharma: Honoraria. Gerds:Imago Biosciences: Research Funding; Roche: Research Funding; Celgene Corporation: Consultancy, Research Funding; Pfizer: Consultancy; CTI Biopharma: Consultancy, Research Funding; Incyte: Consultancy, Research Funding; Sierra Oncology: Research Funding. Sekeres:Syros: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Millenium: Membership on an entity's Board of Directors or advisory committees. Mukherjee:Partnership for Health Analytic Research, LLC (PHAR, LLC): Consultancy; McGraw Hill Hematology Oncology Board Review: Other: Editor; Projects in Knowledge: Honoraria; Celgene Corporation: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Honoraria; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Bristol-Myers Squibb: Speakers Bureau; Takeda: Membership on an entity's Board of Directors or advisory committees.

Clinical and Molecular Characteristics of Acute Myeloid Leukemia (AML) Patients with TP53 Mutations and TP73 Mutations

Introduction: Patients (pts) with AML who harbor TP53 mutations (TP53m) have a poor prognosis, with complete remission (CR) rates of 20-30% with standard intensive cytarabine/daunorubicin induction regimens (7+3) and median disease-free survival (DFS) of 4-6 months. There is a high risk of relapse after allogeneic stem cell transplantation (allo SCT) with 3-year overall survival (OS) of 10-12%. Another member of the p53 family is TP73, expressed as multiple protein isoforms that range in function from tumor suppressive activity to promoting oncogenic activities through control of cell survival and cell renewal. The TP73 gene resides in the short arm of chromosome 1; although this region is frequently deleted in a broad range of tumors, TP73 is rarely mutated in cancer. In the era of next-generation sequencing (NGS), TP73 mutations (TP73m) have not yet been described in AML to our knowledge. Herein we describe AML pts with TP73m and compare their outcomes with those of pts with TP53m and pts without TP73m or TP53m.Methods: Mutational assessment of 81 leukemia- and/or cancer-associated genes using a customized NGS approach was performed on samples from 1165 pts (age ≥18 years) with newly diagnosed AML, treated with standard 7+3 followed by cytarabine +/- anthracycline based consolidation (Eisfeld et al., Leukemia 2017;31:2211-8).We identified 3 groups of pts: wild-type (wt) for both TP53 and TP73,TP53m (including 2 pts with TP73m), and TP73m/TP53wt (TP73m). We made statistical comparisons between groups regarding co-mutations, mutational functional groupings, and outcomes using Fisher's exact test, Kruskal Wallis test, Kaplan-Meier curves, and log rank test.Results: We identified 106 pts with TP53m and 11 pts with TP73m; 1048 pts were confirmed to be wt for both. TP73m pts were all found to have missense mutations, with the majority of variant allele frequencies (VAF) >20%, suggesting these mutations likely represent early mutational events similar to TP53m. Evaluation of mutations in other genes in TP73m pts revealed that most frequent were FLT3-ITD (27%) and mutations in ASXL1 (18%), DNMT3A (18%), IDH2 (18%), NPM1 (36%), RUNX1 (18%), STAG2 (18%), TET2 (27%), and U2AF1 (18%) genes. Frequencies of these mutations were similar to those seen in wt pts, except for higher frequencies of STAG2 (P=.05) and U2AF1 (P=.05) mutations in TP73m pts. No mutation occurred in TP53m pts with a significantly higher frequency than that found in wt pts. However, FLT3-ITD (P<.001), FLT3-TKD (P<.001), and mutations in DNMT3A (P<.001), GATA2 (P=.02), NPM1 (P<.001), SMC1A (P=.04), and WT1 (P<.001) were less frequent in TP53m pts than in wt pts. Compared with TP53m pts, TP73m pts carried NPM1 (P=.005) and U2AF1 (P=.02) mutations more often than TP53m pts.Pretreatment characteristics of pts with TP73m were similar to those of wt pts, except for lower white blood cell counts (WBC) in the former (P=.05). No differences were seen between TP73m and TP53m pts. In contrast, compared with wt pts, TP53m pts were older (P<.001) and presented with lower platelet count (P=.05), WBC (P<.001) and blast percentage of both blood and bone marrow (P<.001 for both), and had less frequent extramedullary involvement (P=.04). Assessment of mutational functional group involvement showed that mutations in chromatin remodeling (P=.004), methylation (P=<.001), and NPM1 (P<.001) were less frequent in TP53m pts than in both TP73m and wt pts. TP53m pts also had fewer mutations in the kinases (P<.001) and RAS pathway (P<.006) compared to wt pts. TP73m pts had more cohesion group mutations than either TP53m (P=.01) or wt pts (P=.04).There were no significant differences in CR, DFS or OS between TP73m and wt pts. However, compared to both TP73m and wt pts, TP53m pts had shorter DFS (P=.005 for TP73m and P<.001 for wt, respectively), event-free survival (EFS) (P=.001 for TP73m and P<.001 for wt, respectively) and OS (P<.001 for both). CR rates of TP53m pts were worse than those of wt pts (P<.001), but there was no significant difference in CR rates between TP53m and TP73m pts (P=.12).Conclusion:TP73m are recurrently found in adult AML pts, albeit with a lower frequency than TP53m. TP73m does not appear to portend the poor prognosis seen in TP53m pts in regards to DFS, EFS and OS and have outcomes that appear to be similar to wt pts.Support: U10CA180821, U10CA180882, U10CA180861, U24CA196171; ClinicalTrials.gov Ids: NCT00048958, NCT00900224 [Display omitted] DisclosuresMims:Agios Pharmaceuticals: Consultancy, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy; Abbvie Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees. Powell:Rafael Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees. Kolitz:Magellan Health: Consultancy, Honoraria.

Abstract 656: Distinct pattern of alterations in TP53 mutated/deleted and wild-type high risk acute myeloid leukemia (AML) patients: Identification of new "targetable" genes/pathways

Abstract Background: The reported TP53 mutation rate in AML is relatively low (7.5-9%, TCGA) and predict a poor prognosis. In 2017 European LeukemiaNet recommended for AML to add TP53 mutations (muts) in the risk stratification. Specific chromosomal aneuploidies are closely correlated with each other and with presence of TP53 muts. Aims: Considering that TP53 mut AML pts have HRisk and no target therapy, we would identify genes/pathways that are mainly CNA-affected (Copy Number Alteration) in the mut TP53 group compared to the wt one. Patients and Methods: 358 adult AML pts were screened for TP53 muts. 219/358 samples were genotyped with SNP arrays. CNA analyses were performed using two software to confirm or integrate karyotype data. Fisher's exact test and pathway enrichment analyses were performed. Results: We detected TP53 muts in 52/358 (14.5%) pts. Mostly (34/52) of the TP53 mut pts (65.4%) had complex karyotype. TP53 alterations were significantly associated with poor outcome (OS and EFS p&amp;lt;0.0001). On TP53 locus, we matched CNA and cytogenetic analyses results. We identify 23 mutated pts that were also deleted (alt) and 7 pts that presented only a TP53 deletion. Therefore 44.2% of mut pts present a concomitant deletion. OS of TP53 alt pts is not statistically inferior respect to mut pts (p=0.77). Comparing 52 TP53 alt and 167 TP53 wt pts CNAs results that: a) chrs significantly altered are 5q and 17p but there are also highly significant »Spot» losses (7q, 20p, 21q, 22q, 19q); b) TP53 CNAs are present in the 44% of TP53 alt vs 0.63% of wt pts; c) over 9013 genes are differentially involved (mainly in Loss, 93.1%); d) that pathway categories mainly enriched are Immune System, Metabolism, Signal Transduction; e) TP53 deletion seems less deleterious (in terms of OS) than TP53 mutation or TP53 alt; f) some TP53 protein-protein interacting genes like SKP1, CDK5, PPP2CA, CSNK1G3 and STAT5B are highly altered and drug target. Conclusions: TP53 muts with or without deletion were predicted to be deleterious and significantly correlated with worse prognosis. For these reasons, TP53 mutation/deletion screening should be recommended. Different alterations groups have been identified in terms of genes, pathway enrichment and protein-protein interaction between ALT and Wt; needed a deeper investigation to better focus on few targetable nodes of this complex network. Three groups comparison (Wt,TP53 Mut,TP53 MutDel pts) analyses would give us the opportunity to select a more appropriate target therapy in these pts. Different pattern of alterations in alt and wt groups have to be deeper investigated to discover targetable nodes of this complex network. ELN, AIL, AIRC, PRIN, Regione-Università 2010-12 (L. Bolondi), FP7 NGS-PTL; HARMONY. Citation Format: Anna Ferrari, Eugenio Fonzi, Andrea Ghelli Luserna Di Rorà, Maria Chiara Fontana, Marco Manfrini, Carmen Baldazzi, Cristina Papayannidis, Vincenza Solli, Antonella Padella, Giovanni Marconi, Stefania Paolini, Valentina Robustelli, Enrica Imbrogno, Eugenia Franchini, Perricone Margherita, Maria Chiara Abbenante, Giorgia Simonetti, Nicoletta Testoni, Emanuela Ottaviani, Michele Cavo, Giovanni Martinelli. Distinct pattern of alterations in TP53 mutated/deleted and wild-type high risk acute myeloid leukemia (AML) patients: Identification of new "targetable" genes/pathways [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 656.

Abstract 1766: Distinct pattern of alterations in tp53 mutated and wild type acute myeloid leukemia (AML) patients

Abstract Background: Mutations in TP53 gene predict a poor prognosis in patients with AML. The reported TP53 mutation rate in AML is low (2.1%) by contrast AML with a complex karyotype (CK) is higher (69-78%) and have a poor outcome. Quite common is to found paired TP53 mutation together and a segmental 17p deletion. Aims: To investigate the frequency, the types of mutations, the associated cytogenetic, the correlation with known molecular alterations and the prognostic role TP53 mutations in adult AML pts. Moreover we would identify genes/pathways that are mainly affected in the mutated TP53 group compared to the wt one. Patients and Methods: 258 adult AML pts with miscellaneous cytogenetic abnormalities and normal karyotype were examined in our Institution for TP53 mutations using several methods, including Sanger sequencing, NGS and HiSeq2000 platform and were correlated with cytogenetic analysis. 124/258 samples were genotyped with SNP arrays (Affymetrix, 3 250K, 43 SNP 6.0, 78 CytoScan HD). Copy Number Alterations (CNAs) analyses were performed using Chromosome Analysis Suite (Affymetrix) and Nexus Copy Number (BioDiscovery) software. Results: Mutation analysis detected TP53 mutations on 39 patients with 48 different types of mutations (32 deleterious point mutations; 4 deletions); nine pts have 2 mutations. We found 34/48 (70%) missense mutations, 5 mutations in the splice sites, 4 deletions ,2 intronic and and 3 others mutations. The mutation rate is of 15.1%. Mostly (28/39) of the TP53 mutated pts (71.8%) had CK while only 11/39 (28.2%) mutated pts have “no CK” (P&amp;gt;0.0001). Alterations of TP53 were significantly associated with poor outcome (OS and EFS p&amp;lt;0.0001). To take advantage of different methodological characteristics, on TP53 locus, we matched two software and cytogenetic analysis results. We identify 16 mutated pts that were also deleted and one pt that presented only a deletion. Therefore 50% of mutated pts present a concomitant deletion. OS of TP53 mutated and deleted pts is statistically inferior respect to muted pts (p&amp;lt;0.0061). Comparing 32 TP53 mutated and 92 TP53 wt pts CNAs results that: a) chromosomes significantly alterated are 5q, 17p, 12p, 16q, 22q13.33 and 7q; b) over 900 genes are differentially involved (all in Loss); c) and that pathway categories mainly enriched are Signal Transduction, Metabolism, Immune System, Transmembrane transport of small molecules, Gene expression, Cell Cycle. Conclusions: Our data demonstrated that TP53 mutations occur in 15.1% of AML with a higher frequency in the subgroup of CK-AML (p&amp;lt;0.0001). They predicted to be deleterious and significantly correlated with worse prognosis especially if TP53 is both mutated and also deleted. For these reasons, TP53 mutation/deletion screening should be recommended. Different pattern of alterations in mutated and wt groups have to be deeper investigated. ELN, AIL, AIRC, progetto Regione-Università 2010-12 (L. Bolondi), FP7 NGS-PTL project. Citation Format: Anna Ferrari, Eugenio Fonzi, Maria Chiara Fontana, Andrea Ghelli Luserna Di Rorà, Marco Manfrini, Antonella Padella, Carmen Baldazzi, Cristina Papayannidis, Giovanni Marconi, Stefania Paolini, Viviana Guadagnuolo, Margherita Perricone, Valentina Robustelli, Enrica Imbrogno, Eugenia Franchini, Claudia Venturi, Elisa Zuffa, Maria Chiara Abbenante, Giorgia Simonetti, Nicoletta Testoni, Emanuela Ottaviani, Martinelli Giovanni. Distinct pattern of alterations in tp53 mutated and wild type acute myeloid leukemia (AML) patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1766. doi:10.1158/1538-7445.AM2017-1766

Postremission Therapy with Repeated Courses of HD-Arac, Idarubicin and Limited Autologous Stem Cell Support Achieves a Very Good Long-Term Outcome in ELN Favourable and Intermediate-Risk AML Except in NPM-Mutated Patients Where Relapse May Occur Even after Five Years

Introduction: Postremission treatment in adult acute myeloid leukemia (AML) is mandatory to improve long-term remission duration. Allogeneic stem-cell transplantation (allo-SCT) is considered gold standard in younger patients (pts) with higher risk of relapse, whereas in pts categorized as standard-risk (SR) AML the optimal treatment remains an open issue. High-dose cytarabine (HD-ARAC) is considered the backbone of postremission treatment in SR AML. The optimal dose and schedule, and the clinical benefit of additional chemotherapeutic agents remain controversial (Schaich, 2011- Lowenberg, 2011- Lowenberg, 2013) as well as the relative efficacy of HD-ARAC in the different cytogenetic and molecular subgroups of SR AML. We analyzed the very long term outcome of consecutive unselected AML pts treated according to AML 00 NILG protocol (Bassan, Blood, 2003: 102; 11) with three repetitive HD-ARAC-based cycles, associated with idarubicin, followed by limited peripheral blood stem cell (PBSC) support, in order to reduce toxicities.Methods: We evaluated 263 consecutive AML pts, diagnosed at our Institution, from January 2001 to March 2016 (median age 52 years - range 15-65). The treatment plan included induction with ICE (Idarubicin-Cytarabine-Etoposide) followed by IC consolidation or HD-ARAC/HD-idarubicin (SPLIT therapy) in refractory cases. ARAC 1g/mq bd for 4 days (A8) was given to CR pts, to collect 3-6x10^6 CD34/kg in 3 aliquots. Patients with ELN favorable or intermediate risk AML, considered SR AML, received 3 cycles of HD-ARAC (2g/mq bd for 5 days) plus idarubicin (8mg/mq for 2 days) with PBSC reinfusion (1-2x10^6 CD34/Kg) (A20). The pts with insufficient CD34 cells yield, received 2 courses HD-ARAC (1g/mq bd for 5 days) plus idarubicin (10mg/mq day 1) (A10). The cumulative dose of ARAC and idarubicin given according to A20 protocol were 69,4 g/mq and 162 mg/mq, respectively.Results: Among 263 pts, 142 (54%) pts were considered SR and 116 (44.1%) HR. Only 5 pts were lacking molecular or cytogenetic information (1.9%) to allow ELN risk classification. Accordingly, 65 pts (25.2%) were favorable [35.4% core binding factor (CBF) positive, 9.2% CEPBA mutated and 55.4% NPM mutated], 87 (33.7%) Intermediate-I, 45 (17.4%) Intermediate II and 61 (23.7%) adverse risk. CR rate after ICE treatment was 77.6% (204/263), 95.8% in SR and 56% in HR pts and after ICE+SPLIT it was 88.2% (232/263); early or aplastic death was 6%. A8 course was administered in 218 pts, of whom 179 were successfully mobilized (82.1%). Among 136 SR pts, 127 were received HD-ARAC (A20 or A10), 4 allo-SCT for early relapse, 3 pts did not proceed to A20 because of prolonged cytopenia and 2 are ongoing. Hematological toxicity was acceptable. ANC recovered at a median of 10 days after CD34+ cells reinfusion. Two death in CR occurred within 100 days after A20 therapy (1.6%). After a median follow-up of 53.3 months (range 1-172), the median survival of SR AML patients was 118.9 months, the DFS and OS at 5 y were 51+/-4.8% and 56.5+/-4.7%, and at 10 y 43.3+/-5.9% and 49.6+/-5.7%, respectively. According to ELN risk, the OS at 5 y and 10 y was 78.3+/-6% and 68+/-8.7% in favorable (median OS not reached), 52.3+/-8% and 46+/-9.4% in Intermediate-I (median OS 118.8 months), and 42+10% and 33.6+/-10.9% in Intermediate-II (median OS 33.1 months) (p0.0034) (Figure1). According to molecular characteristics, the OS at 5-y was 100% in CEBPA-mutated, 77+/-9% (+/-SE) in CBF-mutated and 71+/-11% in NPM-mutated subgroups, respectively (Figure 2). In NPM-mutated pts it was 56+/-14% if FLT3 was mutated and 75+/-10% if not. At 8-y OS was not evaluable in CEBPA-mutated, it remained 77+/-9% in CBF mutated but dropped to 47+/-15% in NPM-mutated pts due to late relapses (28%), which occurred in pts without FLT3. The median time to relapse in NPM pts was 17 m, the latest relapse occurred after 97 months.Conclusion: A postremission program with repeated courses of HD-ARAC associated to idarubicin and limited autologous CD34+ cells support was feasible, well tolerated and very effective, also long-term, in pts with ELN favourable or intermediate risk AML. The late relapse tendency of NPM-mutated AML is puzzling and should be considered by innovative programs aimed at improving these results. [Display omitted] [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Pattern of Central Nervous System (CNS) Involvement in Adult Acute Myeloid Leukemia (AML) and Its Impact on Outcome

▪Background Routine diagnostic lumbar puncture is not recommended in adult patients with acute myeloid leukemia (AML) without Central Nervous System (CNS) symptoms and little is known about the incidence of CNS involvement and its impact on survival in these patients. Furthermore, several studies have demonstrated that flow cytometry (FCM) is superior to conventional cytology (CC) for detection of CNS involvement in lymphoproliferative disorders but the role of this approach for the investigation of cerebrospinal fluid (CSF) in AML is unknown.Design and Methods The aims of our study were 1) to determine the incidence of occult/manifest CNS disease in a homogenous series of AML patients; 2) to correlate CNS disease with clinico-biologic parameters; 3) to examine the impact of CNS involvement on outcome. CSF samples were collected from 98 newly diagnosed AML patients, 62 males and 36 females, median age 53 years (range 18-75). Sixty-five and 33 patients aged <60 and>60 years, respectively.Seventy-one patients received standard and 22 high-dose-ARA-C-based regimens, 5 supportive care. All of 98 CSF samples were examined by CC whereas 90 (91%) also by FCM. CC positivity was defined as unequivocal morphologic evidence of leukemic blast in CSF and/or white blood cells count (WBCc) ≥ 5/µl with less than 10 erythrocytes/µl. A cluster of at least 10 phenotypically abnormal events was regarded as a proof of FCM positivity.Results Sixty-seven patients were CNS negative (CNS-) while thirty-one (31%) were CNS positive (CNS+). Among the last, 10 (10%) were positive on both CC and FCM (manifest CNS+) and 21 (21%) only on FCM (occult CNS+). There was an equal male/female distribution among CNS- and CNS+ patients, as well as median age (52 years, range, 20-71, vs 56 years, range, 18-75, p=NS) and WBCc(27.5 x109/L, range, 1,20-223 x109/L, vs. 11,6 x109/L, range, 0,70-315 x109/L, p= NS) were similar in both groups. Instead, higher levels of lactate dehydrogenase (LDH) were observed among CNS+ than CNS- patients (p=. 01). Forty-seven patients (48%) had monoblastic/monocytic or myelomonocytic AML and belonging to one of these categories was significantly associated with a condition of CNS positivity (55% vs 45%, P = 002). Cytogenetic/genetic data were available in 82/98 (84%). Twenty-for patients (29%), 33 (39%), 12 (14%) and 12 (14%), belonged to the category of favorable, intermediate-I, intermediate-II, and adverse karyotype, respectively. Cytogenetic/genetic characteristics did not differed significantly between CNS+ and CNS- patients. Overall, response rate was 70%, with complete remission rate being not statistically different between CNS+ and CNS- patients (69% vs 81% p= NS). Five-year DFS and OS were found to be significantly shorter in occult or manifest CNS+ patients than in those CNS- (23% vs 50% p= .03 and 19% vs 46%, p=.02, respectively)(Figure 1A and 1B). The prognostic variables achieving a statistical significance in univariate analysis (CNS status, age , WBCc, favorable vs adverse karyotype) were challenged in a multivariate model to determine to what extent they affected treatment outcome. In multivariate analysis, CNS positivity was found to be independently and significantly associated with a shorter duration of DFS.(p=.03 HR= 0.46). Age >50 years was found to be the only independent prognostic factor affecting OS (p=.01 HR= 2.26).Conclusion Our data suggest that incidence of CNS involvement in newly diagnosed AML pts is higher than expected. Regardless of neurologic symptoms, manifest and occult CNS positivity should always be sought at diagnosis since it may affect outcome and influence therapeutic decision. Further prospective studies on larger series are warranted to confirm this data. [Display omitted] [Display omitted] DisclosuresLo Coco:Teva: Consultancy, Honoraria, Speakers Bureau; Lundbeck: Honoraria, Speakers Bureau; Novartis: Consultancy; Baxalta: Consultancy; Pfizer: Consultancy.

Minimal Residual Disease (MRD) As Exploratory Endpoint in a Phase 1 Study of the Anti-CD123 Mab CSL362 Given As Post-Remission Therapy in Adult Acute Myeloid Leukemia (AML)

BackgroundAML patients (pts) who achieve a morphologic complete remission (CR) may have MRD in bone marrow (BM) and/or peripheral blood detected as patient-specific leukemia-aberrant immunophenotype by multiparameter flow cytometry (MFC) or as abnormal transcripts of AML gene mutations/translocations by quantitative RT-PCR. Presence of MRDafter induction and/or consolidation therapy identifies pts at high risk of relapse, with increasing MRD levels indicating impendingrelapse in individual pts. Although standardized testing and validated endpoints for MRD determination across institutions are lacking, major cancer treatment centers can diagnose and track MRD reliablywhen assessed in serial BM samples.CD123 (IL3-Rα) is overexpressed by AML blasts and leukemia stem cells (LSC), suggesting that agents designed to target and kill CD123+ AML LSC and blasts may eliminate MRD and delay or prevent relapse. Retrospective clinical data suggest that conversion of AML pts from MRD + to MRD negative (-) status may confer clinical benefit; however this has not been fully characterized in prospective clinical trials.MethodsCSL362 is a fully humanized, anti-CD123 monoclonal antibody, Fc domain-engineered to bind with high affinity to CD16 on natural killer (NK) cells. CSL362 activates antibody-dependent cell-mediated cytotoxicity (ADCC) of CD123+ cells. The first-in-human Phase 1 study of CSL362 assessed safety, PK and targeted bioactivity. An exploratory objective was to track changes in MRD and to correlate changes with maintenance of CR.Eligible pts had CD123+ de novo or secondary AML in 1st or 2nd CR or CRp who recovered from induction with or without consolidation therapy, had risk factors prognostic for early relapse, and were not candidates for hematopoietic stem cell transplantation. CSL362 was infused IV over 3 hours once every 14 days for up to 6 doses. Sequential pt cohorts were treated at ascending dose levels from 0.3 to 12.0 mg/kg. The final safety evaluation visit was at week (wk) 16, and each center reported remission status at wk 24 from first dose. BMwas assayed for MRD at baseline as well as in wk 5 and wk 12 during therapy according to individual site's laboratory standards using MFC and/or PCR. Changes in MRD were compared to the baseline result for each pt.ResultsEnrollment completed with 30 pts total, in 6 dose level cohorts, treated at 4 hospitals. Safety, PK and biomarker results showing an acceptable safety profile, and targeted bioactivity of CSL362 were reported at the ASH 2014 Annual Meeting [Blood 124 (21); 120]. At baseline, 12 pts were MRD+ (5 by MFC only, 4 by PCR only and 3 by both methods); 11 of 12 had a follow up evaluation. Molecular mutations in post-remission BM identified by PCR were FLT3 (3 pts), NPM1 (3 pts) and MLL (1 pt).Of 4 pts MRD+ by MFC only, 1 converted to MFC- and maintained CR at wk 24. Of 4 pts MRD+ by PCR only, 1 converted to PCR- and maintained CR at wk 24; a 2nd pt, who remained PCR+ on study also maintained CR at wk 24. Of 3 pts MRD+ by both MFC and PCR, 1 converted to MFC-, PCR follow-up was not done but the pt maintained CR at wk 24. The 7 pts MRD+ who did not convert to MRD- relapsed prior to wk 24. [See table].Table 1MRD+ at baselineConverted to MRD - at Wk 5Converted to/Maintained MRD - at Wk 12Maintained CR at Wk 244 + by MFC only1214 + by PCR only (1 FLT3, 1 MLL, 2 NPM1)01 (NPM1)2(NPM1; MLL)3 + by MFC & PCR (2 FLT3, 1 NPM1)by MFC 3by PCR 0by MFC 1by PCR 01 (Flt3)DiscussionConversion from MRD + to MRD - in 4 of 11 pts, with CR maintained at wk 24, is hypothesis generating; MRD conversion suggests possible eradication of residual leukemia cells while on study. Maintenance of morphologic CR was more likely for patients who converted to a MRD-state than those who remained MRD+ during therapy. Multiple factors may affect AML response to CSL362 immunotherapy, including cytogenetic abnormalities, specific molecular mutations, and each pt's immune system status. Preclinical data suggest the activity of CSL362 requires adequate numbers and function of NK cells and expression of the target receptor (CD123) on LSC and MRD cells. This observation would provide validation for the use of MRD response as efficacy endpoint and indicator of benefit for CSL362 and, perhaps, other AML therapies. With further efforts to standardize AML MRD assessments across laboratories, MRD response may become useful as a surrogate endpoint for clinical drug development in AML. DisclosuresDeWitte:CSL Behring: Employment. Dasen:CSL Behring: Employment. Bensen-Kennedy:CSL Behring: Employment. Walter:AstraZeneca, Inc.: Consultancy; Pfizer, Inc.: Consultancy; Amphivena Therapeutics, Inc.: Consultancy, Research Funding; Covagen AG: Consultancy; Seattle Genetics, Inc.: Research Funding; Amgen, Inc.: Research Funding.

Monitoring of Minimal Residual Disease (MRD) of DNMT3A Mutations (DNMT3Amut) in Acute Myeloid Leukemia (AML): A Study of the AML Study Group (AMLSG)

▪Background: The DNA methyltransferase 3A (DNMT3A) is one of the most frequent mutated genes in AML with a hot spot mutation at codon R882 in 80% of the DNMT3Amut cases. In most of the studies DNMT3Amut predicts for poor overall (OS) and relapse-free survival (RFS). Recently, DNMT3Amut have been associated with age-related clonal hematopoiesis, and they have been identified in early preleukemic stem cells. These findings suggest that DNMT3Amut represents an early event in leukemogenesis and may be part of the leukemia founder clone in most AMLs harboring a DNMT3Amut. We thought to address the question whether MRD monitoring in DNMT3Amut patients (pts) can be used for prognostic classification and risk stratification in these pts.Aims: We monitored MRD for the most common DNMT3Amut (DNMT3Amut -R882H, n=126 and -R882C, n=55) in a large cohort of adult AML pts entered on three AMLSG treatment trials [AML HD98A (n=14; NCT00146120), AMLSG 07-04 (n=86; NCT00151242), AMLSG 09-09 (n=81; NCT00893399)].Methods: DNMT3Amut MRD monitoring was performed using a cDNA-based RQ-PCR-assay by TaqMan technology with a sensitivity between 10-3 and 10-4. MRD levels are reported as normalized values of DNMT3Amut transcripts per 104ABL1 transcripts (DNMT3Amut/104ABL1).Results: In total, 1,494 samples [bone marrow (BM), n=798; peripheral blood (PB), n=696] from 181 DNMT3Amut pts were analysed [diagnosis, n=287; during therapy, n=840; follow-up, n=367]. Median age of the patients was 50 years (range, 22 to 78); median BM DNMT3Amut transcript level (TL) at the time of diagnosis was 12690 (range, 1396-54280). There was no significant association of TL with presenting clinical characteristics, such as age, white blood cell count, platelet count, BM and PB blasts, lactate dehydrogenase, or with mutations in NPM1, FLT3 [ITD and TKD], CEBPA and cytogenetics. DNMT3Amut TL as log 10 transformed continuous variable and stratified by study did not impact OS (p=0.29), RFS (p=0.17) and EFS (p=0.28). Comparing TL after double induction (DI) did not show a significant difference between 13 patients without complete remission (CR) and 117 in CR (12983 and 12595, respectively; p=0.52). In Cox regression analyses, BM DNMT3Amut TL as log 10 transformed continuous variable during therapy did not impact the clinical endpoints death and relapse. In general, DNMT3Amut TL during therapy (after induction I, induction II, consolidation I and II) were significantly higher in BM than in PB (p=0.01; p=0.05; p=0.004; p=0.008, respectively). We observed the greatest TL reduction (one log) after induction I, whereas subsequent cycles of therapy did not significantly influence TL. To evaluate the impact of DNMT3Amut MRD monitoring with regard to the clinical endpoints OS, cumulative incidence of relapse (CIR) and remission duration (RD) after DI and after end of therapy (ET) we used different statistical approaches; all survival analyses were stratified by study. After DI and ET, only 8/90 and 4/88 BM samples became MRD negative. At these two time-points MRD positivity did not significantly impact OS (p=0.99; p=0.74), CIR (p=0.73; p=0.15) and RD (p=0.83; p=0.16). Next, we investigated the MRD DNMT3Amut log10-reduction (compared to levels at diagnosis) after DI and ET using the median as a cut-off. Again, we could not detect a significant correlation for pts with a higher TL reduction compared with pts with a lower TL reduction for OS and RD after DI and ET (p=0.83; p=0.30; p=0.04; p=0.21, respectively). Lastly, we evaluated the BM DNMT3Amut TL as 4 increasing equally sized intervals according to the quartiles of the distribution. There was no prognostic impact after DI on OS and RD (p=0.53; p=0.89) and ET (p=0.76; p=0.53). When combining PB and BM samples for the analyses we could not find significant changes in the results.Conclusion: In our study most pts had persistent DNMT3Amut TL with only a minority achieving MRD negativity, a finding that supports the presence of persistent clonal hematopoiesis in hematologic remission. Using different explorative approaches, DNMT3Amut TL did not impact clinical outcome neither during therapy nor during follow-up. DisclosuresHorst:Gilead: Honoraria, Research Funding; Pfizer: Research Funding; MSD: Research Funding; Boehringer Ingleheim: Research Funding; Amgen: Honoraria, Research Funding. Schlenk:Arog: Honoraria, Research Funding; Boehringer-Ingelheim: Honoraria; Janssen: Membership on an entity's Board of Directors or advisory committees; Teva: Honoraria, Research Funding; Pfizer: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; Daiichi Sankyo: Membership on an entity's Board of Directors or advisory committees.