Special considerations in the management of adult patients with acute leukaemias and myeloid neoplasms in the COVID-19 era: recommendations from a panel of international experts

This article is made available for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic.The ongoing COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 is a global public health crisis. Multiple observations indicate poorer post-infection outcomes for patients with cancer than for the general population. Herein, we highlight the challenges in caring for patients with acute leukaemias and myeloid neoplasms amid the COVID-19 pandemic. We summarise key changes related to service allocation, clinical and supportive care, clinical trial participation, and ethical considerations regarding the use of lifesaving measures for these patients. We recognise that these recommendations might be more applicable to high-income countries and might not be generalisable because of regional differences in health-care infrastructure, individual circumstances, and a complex and highly fluid health-care environment. Despite these limitations, we aim to provide a general framework for the care of patients with acute leukaemias and myeloid neoplasms during the COVID-19 pandemic on the basis of recommendations from international experts

Role of neoplastic monocyte-derived fibrocytes in primary myelofibrosis

Primary myelofibrosis (PMF) is a fatal neoplastic disease characterized by clonal myeloproliferation and progressive bone marrow (BM) fibrosis thought to be induced by mesenchymal stromal cells stimulated by overproduced growth factors. However, tissue fibrosis in other diseases is associated with monocyte-derived fibrocytes. Therefore, we sought to determine whether fibrocytes play a role in the induction of BM fibrosis in PMF. In this study, we show that BM from patients with PMF harbors an abundance of clonal, neoplastic collagen- and fibronectin-producing fibrocytes. Immunodeficient mice transplanted with myelofibrosis patients’ BM cells developed a lethal myelofibrosis-like phenotype. Treatment of the xenograft mice with the fibrocyte inhibitor serum amyloid P (SAP; pentraxin-2) significantly prolonged survival and slowed the development of BM fibrosis. Collectively, our data suggest that neoplastic fibrocytes contribute to the induction of BM fibrosis in PMF, and inhibiting fibrocyte differentiation with SAP may interfere with this process

Finding a needle in a haystack: whole genome sequencing and mutation discovery in murine models

Acute promyelocytic leukemia (APL) is a malignancy of the bone marrow, in which there is a deficiency of myeloid cells and an excess of immature cells called promyelocytes. APL is most commonly caused by a translocation (15:17) and expression of the promyelocytic leukemia and the retinoic receptor α (PML-RARA) fusion product; however, the events that cooperate with PML-RARA in APL pathogenesis are not well understood. In this issue of the JCI, Wartman and colleagues use an innovative approach to find other relevant mutations in APL. They performed whole genome sequencing and copy number analysis of a well-characterized APL mouse model to uncover somatic mutations in Jak1 and lysine (K)-specific demethylase 6A (Kdm6a, also known as Utx) in mice with APL and validated the ability of Jak1 mutations to cooperate with PML-RARA in APL. The findings implicate the JAK/STAT pathway in the pathogenesis of APL and illustrate the power of whole genome sequencing to identify novel disease alleles in murine models of disease

Hematologic Malignancies Arising in Patients with Germ Cell Tumors: Secondary Somatic Differentiation of Hematopoietic Malignancies from Germ Cell Precursors

Abstract Genomic analyses have recently illuminated our understanding of therapy-associated myeloid neoplasms in patients receiving therapy for other cancers. One of the most intriguing relationships between solid tumors and myeloid neoplasms involves a unique clinical entity of patients with germ cell tumors (GCT) and myeloid neoplasms. One in 17 patients with primary mediastinal germ cell tumor (PMGCT) develops a hematologic malignancy (most commonly AML, MDS, or histiocytosis) and the median survival in such patients is poor at only 5 months. Intriguingly, the presence of isochromosome 12p [i(12p)], a clonal marker common to GCTs but absent in de novo myeloid neoplasms, has been demonstrated as shared across GCTs and myeloid neoplasms in such individuals. While these data suggest a clonal relationship between the two, the exact nature of the shared origin is unknown. There are two competing hypotheses to explain this: (1) an embryonic progenitor with the capacity to differentiate into germ cell and hematopoietic lineages harbors the initiating genetic alterations and drives development of both malignancies or (2) the leukemia is derived directly from GCTs with the capacity to differentiate into hematopoietic lineages. To trace the clonal evolution of these seemingly unrelated cancer types and identify recurrent genomic lesions in leukemias present in GCT patients, we applied whole exome sequencing (WES), targeted genomic analyses, and/or RNA-seq to leukemias, GCTs, and germline DNA in a series of patients with myeloid neoplasms and concurrent GCTs. We collected 12 patients with GCT and synchronously or metachronously occurring myeloid neoplasms (8 AML, 5 MDS/CMML, 2 histiocytic sarcoma (some had >1 hematologic malignancy)) with an average of 4 months between the two diagnoses. Consistent with prior reports, all were young men (median age 26) with PMGCT and nonseminomatous histology and a 3-month median survival from leukemia diagnosis (Fig. A). In each case, at least one copy number alteration or coding mutation was shared across the GCT and hematopoietic neoplasm, demonstrating the shared origin of both lesions. For example, half of the patients (6/12) carried i(12p) in both the GCT and hematopoietic neoplasm. In the i(12p) negative cases, somatic genetic alterations identified in the GCT were also found in the leukemia. The most common genomic alterations in leukemias beyond i(12p) included mutations activating RAS-PI3K-AKT signaling (including PTEN, RAS and PI3K isoform mutations) or inactivating TP53 (Fig. B). The only exception was a testicular-only GCT patient who developed clonally distinct acute promyelocytic leukemia; however, further analysis identified this as a chemotherapy-induced neoplasm with the PML-RARa breakpoint mapped to an etoposide sensitive area and this patient was not counted amongst the 12 cases. We next traced the evolutionary history of clonally related GCTs and leukemias based on cancer cell fraction of all coding mutations and copy number alterations using WES of DNA from each tumor type and finger nails. In each instance, we identified clonal evolution of the hematopoietic malignancies from antecedent precursors within the GCT. To illustrate this, a 19-year-old male developed successive diagnoses of histiocytic sarcoma, CMML, and AML within 18 months of GCT diagnosis. Lineage tracing by WES of each of these four individual cancers revealed that all four were clonally related, and the histiocytic sarcoma, CMML, and AML were all derived from the GCT with a common precursor giving rise to the three hematopoietic malignancies (Fig. C-D). Moreover, the histiocytic sarcoma evolved separately from CMML/AML in this patient, where the AML represented leukemic transformation from the CMML. These data conclusively demonstrate that myeloid neoplasms developing in patients with PMGCT represent secondary somatic differentiation of a hematologic progenitor from totipotent aberrant cells that are present in the GCT. Thus, GCT-associated leukemias have a unique ontogeny from de novo and/or secondary myeloid neoplasms, which originate from progenitors within the bone marrow. As such, GCT-associated leukemias have characteristic genomic alterations hallmarked by frequent i(12p) in combination with mutations activating RAS-PI3K-AKT signaling and inactivating TP53, and these patients do poorly even when treated with aggressive contemporary chemotherapy. Figure Figure. Disclosures Rampal: Jazz: Consultancy, Honoraria; Celgene: Honoraria; Constellation: Research Funding; Incyte: Honoraria, Research Funding; Stemline: Research Funding. Tallman:ADC Therapeutics: Research Funding; Orsenix: Other: Advisory board; AROG: Research Funding; Cellerant: Research Funding; AbbVie: Research Funding; Daiichi-Sankyo: Other: Advisory board; BioSight: Other: Advisory board

Analysis of the Global Methylation Profile of Accelerated and Blast Phase Myeloproliferative Neoplasms and Its Association with Response to Decitabine-Based Therapy

Methylation profiling in myeloid malignancies such as Acute Myeloid Leukemia (AML) and Chronic Myelomonocytic Leukemia (CMML) has demonstrated the ability to define distinct biological and clinical subgroups, including predicting which patients will respond to therapy with a hypomethylating agent (HMA). The Philadelphia-chromosome negative myeloproliferative neoplasms (MPNs) carry an inherent risk of progression to an accelerated-phase disease (AP; 10-19% blasts in the peripheral blood or bone marrow), as well as to blast phase disease (BP; ≥ 20% blasts in the peripheral blood or bone marrow), which is associated with a poor prognosis. It is unknown whether the methylation profiles of MPN-AP/BP cases may further help identify distinct biological, genomic, and clinical subgroups, including identifying patients more likely to respond to HMA. We recently carried out a phase I/II study to test the safety and efficacy of combination therapy with the JAK1/2 inhibitor ruxolitinib (RUX) and the HMA Decitabine (DAC) in patients with MPN-AP/BP (MPD-RC 109 study; NCT02076191). A total of 46 patients were accrued to the phase I and II studies. 37 patients were evaluable for response. Complete response (CR) occurred in 10%, Complete Response with incomplete count recovery (CRi) in 24%, Partial Response in 24%. 42% of patients had no response to therapy. Using samples available from the MPD-RC 109 study, we sought to assess whether the baseline global methylation profile predicts for response to this regimen. Further, we sought to utilize this dataset to determine if IDH2 mutations (amongst the most common mutations in MPN-AP/BP) are associated with a distinct methylation profile, as has been demonstrated in de novo AML. We carried out a pilot study of 11 MPN-AP/BP patients from the MPD-109 phase I/II trial and performed Enhanced Reduced Representation Bisulfite Sequencing (ERRBS) for DNA methylation quantification at ~3M CpG sites across the genome. Baseline DNA methylation profiles were compared between Responder (R) and Non-responder (NR) patients. Notably, unsupervised analysis using correspondence analysis (COA) demonstrated an almost complete separation of the two groups of patients (Fig 1A), while supervised analysis using a beta binomial model identified 134 differentially methylated regions (DMRs) (FDR25%) between the two groups at diagnosis (Fig 1B). Similar to our prior observation in CMML, response-associated DMRs were depleted from promoter regions (p<0.001) and enriched at enhancers (p<0.001), and were annotated to genes in pathways related to myeloid biology and metabolic processes (Fig 1C). We next carried out a pilot study to characterize the epigenetic abnormalities of IDH2-mutant MPN-AP/BP cases. For this purpose, we compared the genome-wide DNA methylation profiles of 12 IDH2-mutant to 7 IDH1/2 wild type MPN-AP/BP cases using ERRBS. Unsupervised analysis based on the DNA methylation profiles alone showed a strong trend to naturally segregate mutant from wild-type cases, indicating strong underlying epigenetic differences (Fig.1D). A supervised analysis using the beta binomial method identified 1,477 differentially methylated regions (DMRs) between the two groups (average absolute methylation difference ≥25% and FDR <10%) (Fig 1E). Eighty percent of these DMRs corresponded to sites that were hypermethylated in IDH2-mutant cases compared to wild type. These DMRs were strongly enriched in CpG shores and enhancer regions (p value < 0.001 for both) (Fig 1F). Our data demonstrate that the methylation profile of MPN-AP/BP may predict for response to HMA-based therapy. Such data could be used to guide therapeutic decisions and select patient for whom HMA has the highest likelihood of procuring a response. As well, these findings indicate that IDH2-mutant MPN-AP/BP are epigenetically distinct, and given the preferred targeting of regulatory elements, these epigenetic differences may play a functional role in disease biology. Further validation of these observations is required. Updated data, including analysis of further cases, and RNA-sequencing analysis of gene-expression and pathway enrichment of genes differentially methylated between responders and non-responders, and IDH2 mutated and wildtype cases will be presented at the conference. Disclosures Rampal: Constellation: Research Funding; Pharmaessentia: Consultancy; CTI Biopharma: Consultancy; Promedior: Consultancy; Celgene: Consultancy; Incyte: Consultancy, Research Funding; Abbvie: Consultancy; Galecto: Consultancy; Jazz Pharmaceuticals: Consultancy; Blueprint: Consultancy; Stemline: Consultancy, Research Funding. Mascarenhas:Celgene, Prelude, Galecto, Promedior, Geron, Constellation, and Incyte: Consultancy; Incyte, Kartos, Roche, Promedior, Merck, Merus, Arog, CTI Biopharma, Janssen, and PharmaEssentia: Other: Research funding (institution). Levine:Morphosys: Consultancy; Prelude Therapeutics: Research Funding; Novartis: Consultancy; Amgen: Honoraria; Lilly: Consultancy, Honoraria; Janssen: Consultancy; Astellas: Consultancy; Roche: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; Imago: Current equity holder in private company, Membership on an entity's Board of Directors or advisory committees; C4 Therapeutics: Current equity holder in private company, Membership on an entity's Board of Directors or advisory committees; Isoplexis: Current equity holder in private company, Membership on an entity's Board of Directors or advisory committees; Loxo: Current equity holder in private company, Membership on an entity's Board of Directors or advisory committees; Qiagen: Current equity holder in publicly-traded company, Membership on an entity's Board of Directors or advisory committees; Gilead: Honoraria. Hoffman:Novartis: Membership on an entity's Board of Directors or advisory committees; Protagonist: Consultancy; Forbius: Consultancy; Dompe: Research Funding; Abbvie: Membership on an entity's Board of Directors or advisory committees

Telomere Length Is Associated with Specific Mutations and Mutation Classes in Patients with Acute Myeloid Leukemia

Abstract It is unknown if telomere length (TL) is associated with clinical outcome or molecular profile in acute myeloid leukemia (AML). We collected tumor samples from 67 AML patients treated at Memorial Sloan Kettering Cancer Center. DNA extraction was performed using viably frozen peripheral blood and bone marrow mononuclear cells. RainDance was used to amplify all exons of a set of 30 genes commonly mutated in AML. Capture was followed by next-generation sequencing; mutations were called if the variant was supported by >5% of the total number of reads (minimum >10 reads). TL was measured as mean telomere content by qPCR. Patients were assessed for FLT3 and NPM1 mutations, cytogenetics, and outcomes by chart review. Results In our 67 patient AML cohort, median TL was 5.22 kb (range 3.73-8.76). Median age was 64.1 years (range 26.2-84.4). While in healthy individuals TL shortens with age, in our cohort there was no association (R2=0.043). There was no difference in TL between newly diagnosed (ND) and relapsed/refractory (RR) patients or between de novo and secondary AML patients. In the 45 ND patients, there was a trend of early improved survival following sample collection in the longest TL tertile compared to the middle and shortest TL tertiles (86.7% vs. 60.0% and 33.3% at 6 months); however, this association was not statistically significant (p=0.662) (Fig 1). In the 22 RR patients, there was also a trend toward improved OS in the longest TL tertile (60.0% vs. 11.1% and 25.0%, p=0.284). In ND patients, there was no association between TL and primary induction failure or relapse-free survival. Targeted sequencing data for 30 myeloid genes were available in 62 of the 67 patients. Analysis of single mutation correlation with TL showed that patients with IDH1 mutations had significantly longer TL than those without (p=0.02) (Table 1). Moreover, mutations in a set of genes associated with epigenetic functions (IDH1/2, ASXL1, DNMT3A, and TET2) also correlated with longer TL when examined together as a group (p=0.073).FLT3-ITD mutations were associated with shorter TL (p=0.084). The median ages of patients with IDH1 or FLT3 mutations were not different from the rest of the cohort. Of note, FLT3-mutated patients did have a higher WBC than FLT3 wild-type patients (p<0.001), suggesting that increased proliferative rate may be associated with shorter TL. Patients with RUNX1 mutations, t(8;21), or inv(16) also had a non-significant trend toward shorter TL (Table 1), and when we examined FLT3, RUNX1, t(8;21), and inv(16) together as a group, there was an association with shorter TL (p=0.026). There was no association between TL and NPM1 mutations. There was no difference in TL in patients with normal (n=35) vs. abnormal karyotype (n=31). Conclusion There was a trend of early improved survival for patients with the longest TL, suggesting that longer TL may be associated with better response rates to chemotherapy. However, the analysis was limited by the relatively small size of our cohort, andlarger studies are needed to further assess this association. We also demonstrated that IDH1 mutations are associated with longer TL (p=0.02), and that TL in general may be associated with specific classes of AML mutations. For example, mutations in transcription factors or receptor tyrosine kinases conferring a proliferative advantage may be associated with shorter TL, while mutations in epigenetic modifiers appear to be associated with longer TL. This is a novel and intriguing finding that warrants further study of TL, mutational profile, and epigenetic alterations in AML. Table 1 Mutation N Median TL (range) p-value IDH1 0.020 negative 56 5.09 (3.73,8.76) positive 6 6.32 (4.81,7.72) IDH2 0.870 negative 59 5.16 (3.73,8.76) positive 3 5.63 (4.10,6.54) DNMT3A 0.697 negative 53 5.08 (3.73,8.76) positive 9 5.53 (4.53,6.29) TET2 0.423 negative 55 5.16 (3.73,7.85) positive 7 5.53 (4.40,8.76) ASXL1 0.219 negative 59 5.10 (3.73,7.85) positive 3 5.56 (5.52,8.76) FLT3-ITD 0.084 negative 46 5.54 (3.95,8.76) positive 12 4.72 (3.97,8.00) RUNX1 0.856 negative 57 5.22 (3.73,8.76) positive 5 4.89 (4.10,6.34) t(8;21) 0.588 negative 64 5.24 (3.73,8.76) positive 2 4.87 (4.81,4.93) inv(16) 0.302 negative 63 5.22 (3.73,8.76) positive 3 4.72 (4.20,5.26) Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare