High-sensitivity next-generation sequencing MRD assessment in ALL identifies patients at very low risk of relapse.

Measurable residual disease (MRD) is highly prognostic for relapse and overall survival (OS) in acute lymphoblastic leukemia (ALL), although many patients with apparent "MRD negativity" by standard assays still relapse. We evaluated the clinical impact of a highly sensitive next-generation sequencing (NGS) MRD assay in 74 adults with ALL undergoing frontline therapy. Among remission samples that were MRD negative by multiparameter flow cytometry (MFC), 46% were MRD+ by the NGS assay. After 1 cycle of induction chemotherapy, MRD negativity by MFC at a sensitivity of 1 × 10-4 and NGS at a sensitivity of 1 × 10-6 was achieved in 66% and 23% of patients, respectively. The 5-year cumulative incidence of relapse (CIR) among patients who achieved MRD negativity by MFC at complete remission (CR) was 29%; in contrast, no patients who achieved early MRD negativity by NGS relapsed, and their 5-year OS was 90%. NGS MRD negativity at CR was associated with significantly decreased risk of relapse compared with MRD positivity (5-year CIR, 0% vs 45%, respectively; P = .04). Among patients who were MRD negative by MFC, detection of low levels of MRD by NGS identified patients who still had a significant risk of relapse (5-year CIR, 39%). Early assessment of MRD using a highly sensitive NGS assay adds clinically relevant prognostic information to standard MFC-based approaches and can identify patients with ALL undergoing frontline therapy who have a very low risk of relapse and excellent long-term survival.

Real-world diagnostic testing patterns for assessment of ring sideroblasts and SF3B1 mutations in patients with newly diagnosed lower-risk myelodysplastic syndromes.

INTRODUCTION: The presence of ring sideroblasts (RS) and mutation of the SF3B1 gene are diagnostic of lower-risk (LR) myelodysplastic syndromes (MDS) and are correlated with favorable outcomes. However, information on testing and reporting in community-based clinical settings is scarce. This study from the Connect® MDS/AML Disease Registry aimed to compare the frequency of RS and SF3B1 reporting for patients with LR-MDS, before and after publication of the 2016 World Health Organization (WHO) MDS classification criteria. METHODS: Ring sideroblasts assessment and molecular testing data were collected from patients with LR-MDS at enrollment in the Registry. Patients enrolled between December 2013 and the data cutoff of March 2020 were included in this analysis. RESULTS: Among 489 patients with LR-MDS, 434 (88.8%) underwent RS assessment; 190 were assessed prior to the 2016 WHO guidelines (Cohort A), and 244 after (Cohort B). In Cohort A, 87 (45.8%) patients had RS identified; 29 (33.3%) patients had RS < 15%, none of whom underwent molecular testing for SF3B1. In Cohort B, 96 (39.3%) patients had RS identified; 31 (32.3%) patients had < 15% RS, with 13 undergoing molecular testing of which 10 were assessed for SF3B1. CONCLUSIONS: In the Connect® MDS/AML Registry, only 32% of patients with <15% RS underwent SF3B1 testing after the publication of the WHO 2016 classification criteria. There was no change in RS assessment frequency before and after publication, despite the potential impact on diagnostic subtyping and therapy selection, suggesting an unmet need for education to increase testing rates for SF3B1 mutations.

Ultra-accurate Duplex Sequencing for the assessment of pretreatment ABL1 kinase domain mutations in Ph+ ALL.

Mutations of ABL1 are the dominant mechanism of relapse in Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph + ALL). We performed highly accurate Duplex Sequencing of exons 4-10 of ABL1 on bone marrow or peripheral blood samples from 63 adult patients with previously untreated Ph + ALL who received induction with intensive chemotherapy plus a BCR-ABL1 TKI. We identified ABL1 mutations prior to BCR-ABL1 TKI exposure in 78% of patients. However, these mutations were generally present at extremely low levels (median variant allelic frequency 0.008% [range, 0.004%-3.71%] and did not clonally expand and lead to relapse in any patient, even when the pretreatment mutation was known to confer resistance to the TKI received. In relapse samples harboring a TKI-resistant ABL1 mutation, the corresponding mutation could not be detected pretreatment, despite validated sequencing sensitivity of Duplex Sequencing down to 0.005%. In samples under the selective pressure of ongoing TKI therapy, we detected low-level, emerging resistance mutations up to 5 months prior to relapse. These findings suggest that pretreatment ABL1 mutation assessment should not guide upfront TKI selection in Ph + ALL, although serial testing while on TKI therapy may allow for early detection of clinically actionable resistant clones.

Myelodysplastic syndromes following therapy with hypomethylating agents (HMAs): development of acute erythroleukemia may not influence assessment of treatment response.

This study followed 28 patients with myelodysplastic syndromes (MDS) who showed a rise of bone marrow (BM) erythroids to ≥ 50% following three cycles (1-60) of hypomethylating agent (HMA) therapy. If BM blasts were calculated as a percentage of non-erythroids, 12 (42.9%) patients met the diagnostic criteria for acute erythroleukemia, erythroid/myeloid (AEL). However, none of the patients showed clonal cytogenetic evolution or new mutations. When compared to 47 de novo AEL patients, these 12 patients were less anemic and thrombocytopenic, had less complex karyotypes (p = 0.044) and showed a longer survival, either calculated from diagnosis (p < 0.001) or from the time of AEL (p = 0.005). These findings illustrate that ≥ 50% erythroids may appear in BM post-HMA therapy, likely a combination of reduction of BM granulocytes (p < 0.001) and promotion of normal or abnormal erythroid proliferation. Enumeration of blasts as a percentage of non-erythroid cells may lead to a diagnosis of AEL and mis-interpretation as disease progression.

Myelodysplastic syndromes, version 2.2015.

The NCCN Guidelines for Myelodysplastic Syndromes (MDS) comprise a heterogeneous group of myeloid disorders with a highly variable disease course that depends largely on risk factors. Risk evaluation is therefore a critical component of decision-making in the treatment of MDS. The development of newer treatments and the refinement of current treatment modalities are designed to improve patient outcomes and reduce side effects. These NCCN Guidelines Insights focus on the recent updates to the guidelines, which include the incorporation of a revised prognostic scoring system, addition of molecular abnormalities associated with MDS, and refinement of treatment options involving a discussion of cost of care.

Role of reduced-intensity conditioning allogeneic hematopoietic stem-cell transplantation in older patients with de novo myelodysplastic syndromes: an international collaborative decision analysis.

PURPOSE: Myelodysplastic syndromes (MDS) are clonal hematopoietic disorders that are more common in patients aged ≥ 60 years and are incurable with conventional therapies. Reduced-intensity conditioning (RIC) allogeneic hematopoietic stem-cell transplantation is potentially curative but has additional mortality risk. We evaluated RIC transplantation versus nontransplantation therapies in older patients with MDS stratified by International Prognostic Scoring System (IPSS) risk. PATIENTS AND METHODS: A Markov decision model with quality-of-life utility estimates for different MDS and transplantation states was assessed. Outcomes were life expectancy (LE) and quality-adjusted life expectancy (QALE). A total of 514 patients with de novo MDS aged 60 to 70 years were evaluated. Chronic myelomonocytic leukemia, isolated 5q- syndrome, unclassifiable, and therapy-related MDS were excluded. Transplantation using T-cell depletion or HLA-mismatched or umbilical cord donors was also excluded. RIC transplantation (n = 132) stratified by IPSS risk was compared with best supportive care for patients with nonanemic low/intermediate-1 IPSS (n = 123), hematopoietic growth factors for patients with anemic low/intermediate-1 IPSS (n = 94), and hypomethylating agents for patients with intermediate-2/high IPSS (n = 165). RESULTS: For patients with low/intermediate-1 IPSS MDS, RIC transplantation LE was 38 months versus 77 months with nontransplantation approaches. QALE and sensitivity analysis did not favor RIC transplantation across plausible utility estimates. For intermediate-2/high IPSS MDS, RIC transplantation LE was 36 months versus 28 months for nontransplantation therapies. QALE and sensitivity analysis favored RIC transplantation across plausible utility estimates. CONCLUSION: For patients with de novo MDS aged 60 to 70 years, favored treatments vary with IPSS risk. For low/intermediate-1 IPSS, nontransplantation approaches are preferred. For intermediate-2/high IPSS, RIC transplantation offers overall and quality-adjusted survival benefit.