scholarly journals Detection and monitoring of minimal residual disease in acute megakaryoblastic leukemia in children

2021 ◽  
Vol 23 (1) ◽  
pp. 148-155
Author(s):  
Alexandra D. Palladina ◽  
Aleksandr V. Popa ◽  
Timur T. Valiev ◽  
Valentin G. Nikitaev ◽  
Olga A. Chernysheva ◽  
...  

Acute megakaryoblastic leukemia (AMKL) is a rare subtype of acute myeloid leukemia (AML), which is associated with poor prognosis for all patients except children with t(1;22) or Down syndrome. The frequency of complete remission in case of AMKL is comparable to the frequency of complete remission in other variants of AML, and the median survival is much lower. This determines the necessity to update criteria for assessment of the effect of treatment using flow cytometry definition of the level of minimal residual disease (MRD). Nowadays, there are no unified and standardized approaches for the measurement of MRD in case of myeloid leukemia, including AMKL, which prohibits adequate assessment of the therapy effect and in some cases determination of the indications for allogeneic hematopoietic stem cells transplantation. The article identifies diagnostic features and describes approaches for the measurement of the level of MRD in case of AMKL. Aim. The aim is to demonstrate the algorithms for diagnosing and measuring MRD in case of AML-M7 in children. Materials and methods. The article analyzes the clinical and immunological profile of 10 boys and 4 girls with the initial diagnosis of AMKL between the ages of 3 months 12 years old, 13 of them have received treatment in the FSBI N.N. Blokhin National Medical Research Center of Oncology and one in the GBUZ Morozovsky DGKB between 1995 and 2020, The measurement of MRD was carried out in 6 patients. The measurement of MRD was carried out using both morphocytochemical method and multiparameter flow cytometry with megakaryocyte markers (CD61, CD42, CD41) in combination with other myeloid markers (CD13, CD33), CD34, CD117 and aberrant markers (mainly CD7). Results. We showed that adequate measurement of the level of MRD had required detailed immunophenotyping during diagnosis to determine the aberration of megakaryoblasts. CD9 marker (100%), CD33 myeloid marker (69.2%), stem cell antigen CD34 (46.2%), CD13 (38.2%) in addition to megakaryocyte markers (100%) were most often expressed on blast cells in case of AMKL. The CD117 antigen was present on the blasts in 33.3% of cases. The expression of the T-cell-associated CD7 antigen (46.2%) was frequent. The measurement of MRD was carried out during the treatment (usually after an induction course) on the basis of the markers of megakaryocytic cell line (CD61, CD41, CD42a, CD42b), weak CD45 expression, as well as the immunophenotype characteristics during initial diagnosis. The level of MRD ranged from completely negative (0%; 0.006%) to evident (1.05%). Conclusion. The detection of residual tumor megakaryoblasts in case of AML-M7 using flow cytometry is a promising method to evaluate the effect of therapy. The adequate measurement of the level of MRD requires detailed immunophenotyping during the diagnosis to determine the aberration of megakaryoblasts.

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 1015-1015
Author(s):  
Pramod Pinnamaneni ◽  
Jeffrey L. Jorgensen ◽  
Hagop M. Kantarjian ◽  
Elias Jabbour ◽  
Sherry R. Pierce ◽  
...  

Abstract Purpose – To determine the value of Minimal Residual Disease (MRD) assessed by Multi-parameter Flow Cytometry (MFC) after achieving initial response to therapy, in predicting outcome in patients with acute myeloid leukemia (AML) Methods – We investigated the predictive value of MRD assessment by MFC in 191 patients with newly diagnosed AML treated between February 2010 and April 2014 at our institution who had available MRD assessment. MRD by MFC was assessed using an 8-color panel containing 19 distinct markers, on bone marrow specimens obtained at the time of achievement of CR and at approximately 30 days and 90 days after achieving CR. Residual leukemic blasts were identified based on phenotypic differences from normal myelomonocytic precursors. Sensitivity was estimated at 0.1% in most cases, with maximum achievable sensitivity of 0.01%, depending on the leukemic phenotype. Results – Of the 191 patients, 167 (87%) achieved complete remission (CR) or CR without platelet recovery (CRp). Their median age was 58 years (Range, 17-85). 84 (44%) were older than 60 years. Median WBC at presentation was 3.2 x 109/L(Range, 0.5-100.2 x 109/L) and median bone marrow blast percentage was 43% (Range, 11-96%). Cytogenetics was favorable risk in 4 (2%), intermediate risk in130 (68%) and adverse risk in 57 (30%). Treatment included cytarabine plus anthracycline in 170 (89%) and hypomethylating agents-based strategies in 21 (11%). 48 patients had available samples at 30 days post CR and 32 (67%) became MRD negative. Achieving MRD negative status was associated with a statistically significant improvement in CR duration (p=0.02) and overall survival (OS) (p=0.0005). 56 patients were evaluated for MRD status at 90 days and 45 (80%) were negative. Again, achieving MRD negative status was associated with a significant improvement in CR duration (p=0.002) and OS (p=0.0009). Conclusion – Achieving MRD negative status by MFC at 30 and 90 days post CR is associated with an improved outcome in patients with AML Figure 1 Figure 1. Figure 2 Figure 2. Disclosures No relevant conflicts of interest to declare.


2015 ◽  
Vol 139 (10) ◽  
pp. 1276-1280 ◽  
Author(s):  
Michael Keeney ◽  
Jaimie G. Halley ◽  
Daniel D. Rhoads ◽  
M. Qasim Ansari ◽  
Steven J. Kussick ◽  
...  

Context Flow cytometry is often applied to minimal residual disease (MRD) testing in hematolymphoid neoplasia. Because flow-based MRD tests are developed in the laboratory, testing methodologies and lower levels of detection (LODs) are laboratory dependent. Objectives To broadly survey flow cytometry laboratories about MRD testing in laboratories, if performed, including indications and reported LODs. Design Voluntary supplemental questions were sent to the 549 laboratories participating in the College of American Pathologists (CAP) FL3-A Survey (Flow Cytometry—Immunophenotypic Characterization of Leukemia/Lymphoma) in the spring of 2014. Results A total of 500 laboratories (91%) responded to the supplemental questions as part of the FL3-A Survey by April 2014; of those 500 laboratories, 167 (33%) currently perform MRD for lymphoblastic leukemia, 118 (24%) for myeloid leukemia, 99 (20%) for chronic lymphocytic leukemia, and 91 (18%) for plasma cell myeloma. Other indications include non-Hodgkin lymphoma, hairy cell leukemia, neuroblastoma, and myelodysplastic syndrome. Most responding laboratories that perform MRD for lymphoblastic leukemia reported an LOD of 0.01%. For myeloid leukemia, chronic lymphocytic leukemia, and plasma cell myeloma, most laboratories indicated an LOD of 0.1%. Less than 3% (15 of 500) of laboratories reported LODs of 0.001% for one or more MRD assays performed. Conclusions There is major heterogeneity in the reported LODs of MRD testing performed by laboratories subscribing to the CAP FL3-A Survey. To address that heterogeneity, changes to the Flow Cytometry Checklist for the CAP Laboratory Accreditation Program are suggested that will include new requirements that each laboratory (1) document how an MRD assay's LOD is measured, and (2) include the LOD or lower limit of enumeration for flow-based MRD assays in the final diagnostic report.


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