Polygenic Ara-C Response Score Identifies Pediatric Patients With Acute Myeloid Leukemia in Need of Chemotherapy Augmentation.

2022

JCO2101422

2022 Jan 06

1527-7755

<p><strong>PURPOSE: </strong>To establish a patient-specific polygenic score derived from cytarabine (ara-C) pathway pharmacogenomic evaluation to personalize acute myeloid leukemia (AML) treatment.</p>

<p><strong>MATERIALS AND METHODS: </strong>Single nucleotide polymorphisms (SNPs) in the ara-C-pathway genes were analyzed with outcome in patients from the multicenter-AML02 trial (N = 166). Multi-SNP predictor modeling was used to develop 10-SNP Ara-C_SNP score (ACS10) using top SNPs predictive of minimal residual disease and event-free survival (EFS) from the AML02-cohort and four SNPs previously associated with ara-C triphosphate levels in the AML97 trial. ACS10 was evaluated for association with outcomes in each clinical trial arms: the standard low-dose ara-C (LDAC, n = 91) and augmented high-dose ara-C (HDAC, n = 75) arms of AML02 and the standard Ara-C, daunorubicin and etoposide (ADE) (n = 465) and the augmented ADE + gemtuzumab ozogamicin (GO; n = 466) arms of AAML0531 trial.</p>

<p><strong>RESULTS: </strong>In the standard LDAC-arm of AML02 cohort, the low-ACS10 score group (≤ 0) had significantly worse EFS (ACS10 low high hazard ratio [HR] = 2.81; 95% CI, 1.45 to 5.43; = .002) and overall survival (OS; HR = 2.98; 95% CI, 1.32 to 6.75; = .009) compared with the high-ACS10 group (score &gt; 0). These results were validated in the standard-ADE arm of AAML0531, with poor outcome in the low-ASC10 group compared with the high-ACS10 group (EFS: HR = 1.35, 95% CI, 1.04 to 1.75, = .026; OS: HR = 1.64, 95% CI, 1.2 to 2.22, = .002). Within the augmented arms (AML02-HDAC and AAML0531-ADE + GO), EFS and OS did not differ between low- and high-ACS10 score groups. In both cohorts, patients with low-ACS10 consistently showed a 10-percentage point improvement in 5-year EFS with augmented therapy (AML02-HDAC or AAML0531-ADE + GO arms) than with standard therapy (AML02-LDAC or AAML0531-ADE arms).</p>

<p><strong>CONCLUSION: </strong>Patients with low-ACS10 score experienced significantly poor outcome when treated on standard regimen. Augmentation with either high-dose ara-C or GO addition improved outcome in low-ACS10 group. A polygenic ACS10 score can identify patients with unfavorable pharmacogenetic characteristics and offers a potential for an elective augmented therapy option.</p>

10.1200/JCO.21.01422

J Clin Oncol

34990262

CD123 Expression Is Associated With High-Risk Disease Characteristics in Childhood Acute Myeloid Leukemia: A Report From the Children's Oncology Group.

2021

JCO2101595

2021 Dec 02

1527-7755

<p><strong>PURPOSE: </strong>Increased CD123 surface expression has been associated with high-risk disease characteristics in adult acute myeloid leukemia (AML), but has not been well-characterized in childhood AML. In this study, we defined CD123 expression and associated clinical characteristics in a uniformly treated cohort of pediatric patients with newly diagnosed AML enrolled on the Children's Oncology Group AAML1031 phase III trial (NCT01371981).</p>

<p><strong>MATERIALS AND METHODS: </strong>AML blasts within diagnostic bone marrow specimens (n = 1,040) were prospectively analyzed for CD123 protein expression by multidimensional flow cytometry immunophenotyping at a central clinical laboratory. Patients were stratified as low-risk or high-risk on the basis of (1) leukemia-associated cytogenetic and molecular alterations and (2) end-of-induction measurable residual disease levels.</p>

<p><strong>RESULTS: </strong>The study population was divided into CD123 expression-based quartiles (n = 260 each) for analysis. Those with highest CD123 expression (quartile 4 [Q4]) had higher prevalence of high-risk rearrangements and -ITD mutations ( &lt; .001 for both) and lower prevalence of low-risk t(8;21), inv(16), and mutations ( &lt; .001 for all). Patients in lower CD123 expression quartiles (Q1-3) had similar relapse risk, event-free survival, and overall survival. Conversely, Q4 patients had a significantly higher relapse risk (53% 39%, &lt; .001), lower event-free survival (49% 69%, &lt; .001), and lower overall survival (32% 50%, &lt; .001) in comparison with Q1-3 patients. CD123 maintained independent significance for outcomes when all known contemporary high-risk cytogenetic and molecular markers were incorporated into multivariable Cox regression analysis.</p>

<p><strong>CONCLUSION: </strong>CD123 is strongly associated with disease-relevant cytogenetic and molecular alterations in childhood AML. CD123 is a critical biomarker and promising immunotherapeutic target for children with relapsed or refractory AML, given its prevalent expression and enrichment in patients with high-risk genetic alterations and inferior clinical outcomes with conventional therapy.</p>

10.1200/JCO.21.01595

J Clin Oncol

34855461

CBFB-MYH11 Fusion Transcripts Distinguish Acute Myeloid Leukemias with Distinct Molecular Landscapes and Outcomes.

2021

2021 Sep 21

2473-9537

<p>Patients with inv(16)/CBFB-MYH11 AML are considered favorable risk, however, nearly one-third relapse despite intensive therapy. Despite efforts to define risk groups within this favorable risk cohort, CBFB-MYH11 AML patients continue to be treated as a uniform cohort. Through transcriptome sequencing of 186 patients with inv(16) AML, we demonstrate that fusion junction breakpoints (exon 5-exon 33 versus other) are highly associated with outcome. The presence of exon 17 KIT mutations provides additional prognostic significance. Additionally, we provide insights into the transcriptional landscapes that differentiate these distinct CBFB-MYH11 AML subtypes. Children's Oncology Group trials include CCG-2961 (registered at www.clinicaltrials.gov as NCT00002798), AAML03P1 (NCT00070174), AAML0531 (NCT00372593), and AAML1031 (NCT01371981).</p>

10.1182/bloodadvances.2021004965

Blood Adv

34547772

Outcomes of intensification of induction chemotherapy for children with high-risk acute myeloid leukemia: A report from the Children's Oncology Group.

2021

e29281

2021 Oct 01

1545-5017

<p><strong>BACKGROUND: </strong>High-risk pediatric acute myeloid leukemia confers a poor prognosis, and alternative strategies are needed to improve outcomes. We hypothesized that intensifying induction on the AAML1031 clinical trial would improve outcomes compared to the predecessor trial AAML0531.</p>

<p><strong>METHODS: </strong>Patients on AAML0531 received cytarabine (1600&nbsp;mg/m )/daunorubicin (150&nbsp;mg/m )/etoposide (ADE) for induction II and patients on AAML1031 received mitoxantrone (48&nbsp;mg/m )/cytarabine (8000&nbsp;mg/m ) (MA). Stem cell transplant (SCT) conditioning included busulfan/cyclophosphamide on AAML0531, whereas AAML1031 used busulfan/fludarabine and liberalized donor eligibility. Patients were included in this analysis if they met high-risk criteria common to the two trials by cytogenics or poor disease response after induction I ADE.</p>

<p><strong>RESULTS: </strong>MA provided no benefit over ADE at: induction II response (complete response [CR]: 64% vs. 62%, p&nbsp;=&nbsp;.87; measurable residual disease [MRD]+: 57% vs. 46%, p&nbsp;=&nbsp;.34); or intensification I response (CR: 79% vs. 94%, p&nbsp;=&nbsp;.27; MRD+: 27% vs. 20%, p&nbsp;=&nbsp;1.0). When considered with altered SCT approach, MA did not improve 5-year disease-free survival (24% ± 9% vs. 18% ± 15%, p&nbsp;=&nbsp;.63) or 5-year overall survival (35% ± 10% vs. 38% ± 18%, p&nbsp;=&nbsp;.66). MA was associated with slower neutrophil recovery (median 34 vs. 27&nbsp;days, p&nbsp;=&nbsp;.007) and platelet recovery (median 29 vs. 24.5&nbsp;days, p&nbsp;=&nbsp;.04) and longer hospital stay (32 vs. 28&nbsp;days, p&nbsp;=&nbsp;.01) during induction II.</p>

<p><strong>CONCLUSION: </strong>Intensification of induction II did not improve treatment response or survival, but did increase toxicity and resource utilization. Alternative strategies are urgently needed to improve outcomes for pediatric patients with high-risk acute myeloid leukemia (trials registered at clinicaltrials.gov NCT01371981, NCT00372593).</p>

10.1002/pbc.29281

Pediatr Blood Cancer

34596937

Cytarabine dose reduction in patients with low-risk acute myeloid leukemia: A report from the Children's Oncology Group.

2021

e29313

2021 Sep 02

1545-5017

<p><strong>BACKGROUND: </strong>The optimal number of chemotherapy courses for low-risk (LR) pediatric acute myeloid leukemia (AML) is not known.</p>

<p><strong>OBJECTIVE: </strong>To compare outcomes for four (21.6&nbsp;g/m cytarabine) versus five (45.6&nbsp;g/m cytarabine) chemotherapy courses for LR-AML using data from Children's Oncology Group (COG) AAML0531 and AAML1031.</p>

<p><strong>METHODS: </strong>We compared relapse risk (RR), disease-free survival (DFS), and overall survival (OS), and the differential impact in LR subgroups for patients receiving four versus five chemotherapy courses. Cox (OS and DFS) and risk (RR) regressions were used to estimate hazard ratios (HR) to compare outcomes.</p>

<p><strong>RESULTS: </strong>A total of 923 LR-AML patients were included; 21% received five courses. Overall, LR-AML patients who received four courses had higher RR (40.9% vs. 31.4%; HR&nbsp;=&nbsp;1.40, 95% confidence interval [CI]: 1.06-1.85), and worse DFS (56.0% vs. 67.0%; HR&nbsp;=&nbsp;1.45, 95% CI: 1.10-1.91). There was a similar decrement in OS though it was not statistically significant (77.0% vs. 83.5%; HR&nbsp;=&nbsp;1.45, 95% CI: 0.97-2.17). Stratified analyses revealed the detrimental effects of cytarabine dose de-escalation to be most pronounced in the LR-AML subgroup with uninformative cytogenetic/molecular features who were minimal residual disease (MRD) negative after the first induction course (EOI1). The absolute decrease in DFS with four courses for patients with favorable cytogenetic/molecular features and positive MRD was similar to that observed for patients with uninformative cytogenetic/molecular features and negative MRD at EOI1, though not statistically significant.</p>

<p><strong>CONCLUSIONS: </strong>Our results support de-escalation of cytarabine exposure through the elimination of a fifth chemotherapy course only for LR-AML patients who have both favorable cytogenetic/molecular features and negative MRD after the first induction cycle.</p>

10.1002/pbc.29313

Pediatr Blood Cancer

34472213

Survival Following Relapse in Children with Acute Myeloid Leukemia: A Report from AML-BFM and COG.

2021

2021 May 12

2072-6694

<p>Post-relapse therapy remains critical for survival in children with acute myeloid leukemia (AML). We evaluated survival, response and prognostic variables following relapse in independent cooperative group studies conducted by COG and the population-based AML-BFM study group. BFM included 197 patients who relapsed after closure of the last I-BFM relapse trial until 2017, while COG included 852 patients who relapsed on the last Phase 3 trials (AAML0531, AAML1031). Overall survival at 5 years (OS) was 42 ± 4% (BFM) and 35 ± 2% (COG). Initial high-risk features (BFM 32 ± 6%, COG 26 ± 4%) and short time to relapse (BFM 29 ± 4%, COG 25 ± 2%) predicted diminished survival. In the BFM dataset, there was no difference in OS for patients who had a complete remission with full hematopoietic recovery (CR) following post-relapse re-induction compared to those with partial neutrophil and platelet recovery (CRp and CRi) only (52 ± 7% vs. 63 ± 10%, = 0.39). Among 90 patients alive at last follow-up, 87 had received a post-relapse hematopoietic stem cell transplant (HSCT). OS for patients with post-relapse HSCT was 54 ± 4%. In conclusion, initial high-risk features and early relapse remain prognostic. Response assessment with full hematopoietic recovery following initial relapse therapy does not predict survival. These data indicate the need for post-relapse risk stratification in future studies of relapse therapies.</p>

10.3390/cancers13102336

Cancers (Basel)

34066095

Gemtuzumab Ozogamicin Improves Event-Free Survival and Reduces Relapse in Pediatric -Rearranged AML: Results From the Phase III Children's Oncology Group Trial AAML0531.

2021

JCO2003048

2021 May 28

1527-7755

<p><strong>PURPOSE: </strong>We investigated the impact of the CD33-targeted agent gemtuzumab ozogamicin (GO) on survival in pediatric patients with -rearranged (-r) acute myeloid leukemia (AML) enrolled in the Children's Oncology Group trial AAML0531 (NCT01407757).</p>

<p><strong>METHODS: </strong>Patients with -r AML were identified and clinical characteristics described. Five-year overall survival (OS), event-free survival (EFS), disease-free survival (DFS), and relapse risk (RR) were determined overall and for higher-risk versus not high-risk translocation partners. GO's impact on response was determined and outcomes based on consolidation approach (hematopoietic stem cell transplant [HSCT] chemotherapy) described.</p>

<p><strong>RESULTS: </strong>Two hundred fifteen (21%) of 1,022 patients enrolled had -r AML. Five-year EFS and OS from study entry were 38% and 58%, respectively. EFS was superior with GO treatment (EFS 48% with GO 29% without, = .003), although OS was comparable (63% 53%, = .054). For patients with -r AML who achieved complete remission, GO was associated with lower RR (40% GO 66% patients who did not receive GO [No-GO], = .001) and improved 5-year DFS (GO 57% No-GO 33%, = .002). GO benefit was observed in both higher-risk and not high-risk -r subsets. For patients who underwent HSCT, prior GO exposure was associated with decreased relapse (5-year RR: 28% GO and HSCT 73% No-GO and HSCT, = .006). In multivariable analysis, GO was independently associated with improved EFS, improved DFS, and reduced RR.</p>

<p><strong>CONCLUSION: </strong>GO added to conventional chemotherapy improved outcomes for -r AML; consolidation with HSCT may further enhance outcomes. Future clinical trials should study CD33-targeted agents in combination with HSCT for pediatric r AML.</p>

10.1200/JCO.20.03048

J Clin Oncol

34048275

CEBPA bZip Mutations are Associated with Favorable Prognosis in de novo AML: A Report from the Children's Oncology Group.

2021

2021 May 05

1528-0020

<p>Bi-allelic CEBPA mutations are associated with favorable outcomes in AML. We evaluated the clinical and biologic implications of CEBPA-bZip mutations in childhood/young adult newly diagnosed AML. CEBPA-bZip mutation status was determined in 2,958 AML patients enrolled on COG trials (NCT00003790, NCT0007174, NCT00372593, NCT01379181). Next generation sequencing (NGS) was performed in 1,863 patients, 107 with CEBPA mutations, to characterize the co-occurring mutations. CEBPA mutational status was correlated with disease characteristics and clinical outcomes. CEBPA-bZip mutations were identified in 160/2958 (5.4%) patients, with 132 (82.5%) harboring a second CEBPA mutation (CEBPA-dm) and 28 (17.5%) with a single CEBPA-bZip only. The clinical and laboratory features of the two CEBPA cohorts were very similar. CEBPA-dm and CEBPA-bZip patients experienced identical event-free survival (EFS) of 64% and similar overall survival (OS) of 81% and 89%, respectively (p=0.259); this compared favorably to EFS and OS in CEBPA wild type (CEBPA-WT) of 46% and 61%, respectively (both p&lt;0.001). Transcriptome analysis demonstrated similar expression profiles for CEBPA-bZip and CEBPA-dm cases. Comprehensive NGS of CEBPA-mutant cases identified co-occurring CSF3R and GATA2 mutations in 13.1% and 21.5% of patients, respectively. Patients with dual CEBPA/CSF3R mutations had an EFS of 17% vs. 63% for CEBPA-mutant/CSF3R-WT (p&lt;0.001) with a corresponding relapse rate (RR) of 83% vs. 22%, respectively (p&lt;0.001); GATA2 co-occurrence did not impact outcome. CEBPA bZip domain mutations are associated with favorable clinical outcomes, regardless of mono or bi-allelic status. Co-occurring CSF3R and CEBPA mutations are associated with a high RR and nullifies the favorable prognostic impact of CEBPA mutations.</p>

10.1182/blood.2020009652

Blood

33951732

Acute erythroid leukemia is enriched in NUP98 fusions: a report from the Children's Oncology Group.

2020

6000-6008

2020 Dec 08

2473-9537

<p>Acute erythroid leukemia (AEL) is a rare subtype of acute myeloid leukemia (AML) primarily affecting older adults and was previously classified into erythroid/myeloid and pure erythroid subtypes. In this pediatric AEL study, we evaluated morphologic, immunophenotypic, cytogenetic, molecular, and clinical data of 24 (1.2%) cases from all cases undergoing central pathology review in Children's Oncology Group trials AAML0531 and AAML1031. Of 24 cases, 5 had a pure erythroid phenotype, and 19 had an erythroid/myeloid phenotype. NUP98 fusions were highly enriched in patients with AEL, occurring in 7 of 22 cases for which molecular data were available (31.8% vs 6.7% in other AML subtypes). Of 5 cases of pure erythroid leukemias (PELs), 3 had NUP98 fusions, and 4 had complex karyotypes. Erythroid/myeloid leukemias were reclassified by using the 2017 World Health Organization hematopathology classification as: myelodysplastic syndrome (MDS) with excess blasts-1 (n = 3), MDS with excess blasts-2 (n = 7), AML (nonerythroid, n = 5), and unknown MDS/AML (n = 4); the 5 cases of nonerythroid AML included 1 with an NUP98-NSD1 fusion, 2 with myelodysplasia-related changes, and 1 with a complex karyotype. Three cases of MDS with excess blasts-2 also had NUP98 rearrangements. WT1 mutations were present in 5 of 14 cases, all erythroid/myeloid leukemia. Outcomes assessment revealed statistically poorer overall survival (5-year, 20% ± 36% vs 66% ± 23%; P = .004) and event-free survival (5-year, 20% ± 36% vs 46% ± 23%; P = .019) for those with PEL than those with erythroid/myeloid leukemia. Our study supports that AEL is a morphologically and genetically heterogeneous entity that is enriched in NUP98 fusions, with the pure erythroid subtype associated with particularly adverse outcomes.</p>

10.1182/bloodadvances.2020002712

Blood Adv

33284945

Heat Shock Factor 1 (HSF1-pSer326) Predicts Response to Bortezomib-Containing Chemotherapy in Pediatric AML: A COG Study.

2020

2020 Sep 21

1528-0020

<p>Bortezomib (BTZ) was recently evaluated in a randomized Phase 3 clinical trial which compared standard chemotherapy (cytarabine, daunorubicin, etoposide; ADE) to standard therapy with BTZ (ADEB) for de novo pediatric acute myeloid leukemia. While the study concluded that BTZ did not improve outcome overall, we examined patient subgroups benefitting from BTZ-containing chemotherapy using proteomic analyses. The proteasome inhibitor BTZ disrupts protein homeostasis and activates cytoprotective heat shock responses. We measured total heat shock factor 1 (HSF1) and phosphorylated HSF1 (HSF1-pSer326) in leukemic cells from 483 pediatric patients using Reverse Phase Protein Arrays. HSF1-pSer326 phosphorylation was significantly lower in pediatric AML compared to CD34+ non-malignant cells. We identified a strong correlation between HSF1-pSer326 expression and BTZ sensitivity. BTZ significantly improved outcome of patients with low-HSF1-pSer326 with a 5-year event-free survival of 44% (ADE) vs. 67% for low-HSF1-pSer326 treated with ADEB (P=0.019). To determine the effect of HSF1 expression on BTZ potency in vitro, cell viability with HSF1 gene variants that mimicked phosphorylated (S326A) and non-phosphorylated (S326E) HSF1-pSer326 were examined. Those with increased HSF1 phosphorylation showed clear resistance to BTZ vs. those with wild type or reduced HSF1-phosphorylation. We hypothesize that HSF1-pSer326 expression could identify patients that benefit from BTZ-containing chemotherapy.</p>

10.1182/blood.2020005208

Blood

32959058