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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., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The interplay between tumor heterogeneity and microenvironmental factors is a critical mechanism for clonal selection in leukemia. Evidence of unique clonal capacities to engraft within patient-derived xenograft (PDX) models suggests that intrapatient genetic architecture may be defined by functional differences at the clonal level. However, methods to detect functional differences assigned to genetically defined clones remain limited. Here, we describe a scalable method to directly measure the functional properties of clones within the same leukemia patient by coupling intracellular flow cytometry and next-generation sequencing (NGS). We provide proof of concept utilizing primary chronic myelmonocytic leukemia (CMML) samples and granulocyte-macrophage colony stimulating factor (GM-CSF) to elucidate the interaction between tumor heterogeneity and microenvironmental factors. Mixtures of human leukemia cell lines, with known response to GM-CSF, were used to validate the accuracy of our methodology. Using this approach, we confirm that our method is capable of discriminating GM-CSF sensitive cell lines, identifies somatic variants in primary leukemia samples, and resolves functional clonal architecture in an illustrative patient. Taken together, our data describes a novel method to determine intrapatient functional clonal heterogeneity and provides proof-of-concept for future investigation aimed at elucidating the clinical relevance of functional clonal differences.

Background: Transfusion of blood products is a key component of the supportive management in patients with acute leukemia (AL). However high-quality trial evidence and clinical outcome data to support specific transfusion goals for blood products for patients with AL remain limited leading to diverse transfusion practices. The primary objective of this study was to determine the spectrum of transfusion patterns in a variety of care settings among providers who treat AL patients., Study Design and Methods: A 31-question survey queried providers caring for AL patients about the existence of institutional guidelines for transfusion of blood products, transfusion triggers for hemoglobin (Hb), platelets (PLTs), and fibrinogen in various settings including inpatient and outpatient and before procedures., Results: We analyzed 130 responses and identified divergent transfusion Hb goals in hospitalized and ambulatory patients, fibrinogen goals for cryoprecipitate transfusions, and variation in practice for use of certain PLTs and red blood cell products. The least variable transfusion patterns were reported for PLT goals in thrombocytopenia and in the setting of invasive procedures such as bone marrow biopsy and lumbar punctures., Conclusions: This survey confirmed wide variations in blood product transfusion practices across several clinical scenarios in patients with AL. The findings emphasized the need for large prospective randomized trials to develop standardized evidence-based guidelines for blood product transfusions in patients with AL with the goal of limiting unnecessary transfusions without compromising outcomes., (© 2016 AABB.)

Telomeres are specialized structures providing chromosome integrity during cellular division along with protection against premature senescence and apoptosis. Accelerated telomere attrition in patients with myelodysplastic syndrome (MDS) occurs by an undefined mechanism. Although the MDS clone originates within the myeloid compartment, T-lymphocytes display repertoire contraction and loss of naive T-cells. The replicative lifespan of T-cells is stringently regulated by telomerase activity. In MDS cases, we show that purified CD3+ T-cells have significantly shorter telomere length and reduced proliferative capacity upon stimulation compared with controls. To understand the mechanism, telomerase enzymatic activity and telomerase reverse transcriptase (hTERT), gene expression were compared in MDS cases (n=35) and healthy controls (n=42) within different T-cell compartments. Telomerase activity is greatest in naive T-cells illustrating the importance of telomere repair in homeostatic repertoire regulation. Compared with healthy controls, MDS cases had lower telomerase induction (P<0.0001) that correlated with significantly lower hTERT mRNA (P<0.0001), independent of age and disease stratification. hTERT mRNA deficiency affected naive but not memory T-cells, and telomere erosion in MDS occurred without evidence of an hTERT-promoter mutation, copy number variation or deletion. Telomerase insufficiency may undermine homeostatic control within the hematopoietic compartment and promote a change in the T-cell repertoire in MDS. [ABSTRACT FROM AUTHOR]