flow cytometry

Technical Aspects of Minimal Residual Disease Detection by Multicolor Flow Cytometry in Acute Myeloid Leukemia Patients

AUTOIMMUNE THROMBOCYTOPENIA , ,

IV Galtseva, YuO Davydova, NM Kapranov, KA Nikiforova, EN Parovichnikova

National Research Center for Hematology, 4 Novyi Zykovskii pr-d, Moscow, Russian Federation, 125167

For correspondence: Yuliya Olegovna Davydova, MD, PhD, 4 Novyi Zykovskii pr-d, Moscow, Russian Federation, 125167; Tel.: 8(495)612-62-21; e-mail: juliya89mur@yandex.ru

For citation: Galtseva IV, Davydova YuO, Kapranov NM, et al. Technical Aspects of Minimal Residual Disease Detection by Multicolor Flow Cytometry in Acute Myeloid Leukemia Patients. Clinical oncohematology. 2021;14(3):503–12. (In Russ).

DOI: 10.21320/2500-2139-2021-14-4-503-512

ABSTRACT

Detection and monitoring of minimal residual disease (MRD) are essential components of programmed therapy.They are crucial for the choice of treatment strategy and for prognostic purposes practically in all hematologic diseases. MRD is often detected by multicolor flow cytometry, the method with fairly high specificity and sensitivity. However, to identify MRD in acute myeloid leukemia patients is one of the most challenging tasks flow cytometry specialists are faced with. Cytometric data analysis requires the expert knowledge of immunophenotype of all maturing bone marrow cells. Besides, MRD analysis in acute myeloid leukemia has not been standardized while approaches suggested by different studies vary considerably. The present paper reports the experience of MRD analysis, demonstrates the gating strategy, immunophenotype description of normal non-tumor hematopoietic cells, and presents some examples of MRD assessment. Additionally, panels of monoclonal antibodies are provided, along with an evaluation of their advantages and disadvantages.

Keywords: minimal residual disease, acute myeloid leukemias, flow cytometry, gating, immunophenotyping.

Received: June 9, 2021

Accepted: September 5, 2021

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Статистика Plumx английский

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Role of Superficial CD200 Marker in Differential Diagnosis of Malignant B-Cell Lymphoproliferative Diseases

LYMPHOID TUMORS , , , , ,

YuV Mirolyubova, EA Stadnik, TS Nikulina, VV Strugov, TO Andreeva, YuV Virts, RV Grozov, AYu Zaritskey

Federal Almazov North-West Medical Research Centre, 2 Akkuratova str., Saint Petersburg, Russian Federation, 197341

For correspondence: Yuliya Vladimirovna Mirolyubova, 2 Akkuratova str., Saint Petersburg, Russian Federation, 197341; e-mail: juli9702@yandex.ru

For citation: Mirolyubova YuV, Stadnik EA, Nikulina TS, et al. Role of Superficial CD200 Marker in Differential Diagnosis of Malignant B-Cell Lymphoproliferative Diseases. Clinical oncohematology. 2017;10(2):169–75 (In Russ).

DOI: 10.21320/2500-2139-2017-10-2-169-175

ABSTRACT

Background & Aims. Flow cytometry is successfully used for diagnosis of malignant lymphoproliferative disorders. However, there are atypical cases that are difficult to interpret; thus, new markers relevant for the differential diagnosis are to be searched for. The aim is to analyze CD200 expression in patients with B-cell lymphoproliferative disorders.

Materials & Methods. 187 patients with chronic lymphocytic leukemia (CLL), 14 patients with mantle cell lymphoma (MCL), 9 patients with marginal zone lymphoma (MZL), and 5 patients with hairy cell leukemia (HCL) were enrolled in the study. Neoplasm was not confirmed in 12 subjects. The patients underwent the following tests: CBC, immunophenotyping of peripheral blood or bone marrow lymphocytes, and a cytogenetic test. In some cases, an additional immunohistochemical test of bone marrow trepanobiopsy or lymph node biopsy samples was required.

Results. In all cases of CLL and HCL, the CD200 expression was positive; mean fluorescence intensity was higher in these cases as compared to other groups. Negative expression of CD200 prevailed in MCL patients; however, at the same time 2 cases of intermediate and positive expression were reported, both showing moderate fluorescence intensity values. CD200 expression was heterogeneous in MZL patients.

Conclusion. The CD200 negative expression excludes typical HCL and CLL. Additional cytogenetic and immunnohistoсhemical tests should be performed in such cases to verify the diagnosis, first of all, MCL or MZL.

Keywords: CD200, flow cytometry, diagnosis, chronic lymphocytic leukemia, mantle cell lymphoma, marginal zone lymphoma, hairy cell leukemia.

Received: September 7, 2016

Accepted: January 3, 2017

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Acute Leukemias: Immunophenotypic Differences between Blast Cells and Their Nonneoplastic Analogues in Bone Marrow

LYMPHOID TUMORS , , ,

АM Popov1, ТYu Verzhbitskaya2,3, LG Fechina2, AV Shestopalov1,4, SA Plyasunova1

1 Dmitrii Rogachev Federal Scientific Clinical Centre of Pediatric Hematology, Oncology and Immunology, 1 Samory Mashela str., Moscow, Russian Federation, 117997

2 Regional Children’s Hospital No. 1, 32 Serafimy Deryabinoi str., Yekaterinburg, Russian Federation, 620149

3 Institute of Medical Cell Technologies, 22a Karla Marksa str., Yekaterinburg, Russian Federation, 620026

4 N.I. Pirogov Russian National Research Medical University, 1 Samory Mashela str., Moscow, Russian Federation, 117997

For correspondence: Aleksandr Mikhailovich Popov, PhD, 1 Samory Mashela str., Moscow, Russian Federation, 117997; Tel.: +7(495)287-65-70; e-mail: uralcytometry@gmail.com

For citation: Popov AM, Verzhbitskaya TYu, Fechina LG, et al. Acute Leukemias: Immunophenotypic Differences between Blast Cells and Their Nonneoplastic Analogues in Bone Marrow. Clinical oncohematology. 2016;9(3):302-13 (In Russ).

DOI: http://dx.doi.org/10.21320/2500-2139-2016-9-3-302-313

ABSTRACT

Flow cytometry immunophenotyping of bone marrow tumor blasts is one of the principal methods used for acute leukemia (AL) diagnosing. Normal lymphopoietic and myelopoietic progenitors have very similar antigenic profile with leukemic cells, thus, making the AL diagnosing more difficult. Genetic disorders resulting in formation of a tumor clone contribute to development of an immunophenotype that differs from normal cells. Aberrant expression of markers detected in AL blast cells alone forms a so-called leukemia-associated immunophenotype. The leukemia-associated immunophenotype detection by multicolor flow cytometry permits distinguishing between normal and neoplastic cells. This requires simultaneous assessment of many markers on the same cells, which is possible only if multicolor flow cytometry with well-designed and well-established antibodies panels is used. Moreover, correct interpretation of the cell population location on dot plot requires adequate cytometer setup, standardized sample preparation and enough experienced personnel. That is why correct immunophenotyping is often possible only in large laboratories performing reference immunophenotyping within the frames of multicenter trials.

Keywords: acute leukemias, flow cytometry, antigenic expression, immunophenotype.

Received: February 19, 2016

Accepted: March 16, 2016

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Chronic Lymphocytic Leukemia: Prognostic Significance of Minimal Residual Disease and Potential of Modern Methods of Its Diagnosis and Therapy (Literature Review)

LYMPHOID TUMORS , ,

AYu Kuvshinov, SV Voloshin, IS Martynkevich, EV Kleina, MA Mikhaleva, KM Abdulkadyrov

Russian Scientific Research Institute of Hematology and Transfusiology, 16 2-ya Sovetskaya str., Saint Petersburg, Russian Federation, 191024

For correspondence: Sergei Vladimirovich Voloshin, PhD, 16 2-ya Sovetskaya str., Saint Petersburg, Russian Federation, 191024; Tel.: +7(812)274-37-70; e-mail: kuvshinovmd@gmail.com

For citation: Kuvshinov AYu, Voloshin SV, Martynkevich IS, et al. Chronic Lymphocytic Leukemia: Prognostic Significance of Minimal Residual Disease and Potential of Modern Methods of Its Diagnosis and Therapy (Literature Review). Clinical oncohematology. 2016;9(2):191–8 (In Russ).

DOI: 10.21320/2500-2139-2016-9-2-191-198

ABSTRACT

Achieving a complete remission (CR) in patients with chronic lymphocytic leukemia (CLL) has become a feasible goal directly correlating with a prolonged survival. However, a certain number of tumor cells may be present in the patient’s body even when CR has been achieved, and this phenomenon is called a minimal residual disease (MRD). A lot of data confirming the necessity of MRD diagnosing and monitoring has emerged recently, since the MRD has a significant impact on the prognosis of CLL. Achieving MRD-negative remission is an independent predictor of long-term progression-free survival and overall survival. The occurrence of new diagnostic techniques has allowed to define the MRD and to develop standards for its assessment. This paper presents an overview of literature data about MRD, methods of its evaluation, prognostic significance, as well as the methods of eradication.

Keywords: chronic lymphocytic leukemia, minimal residual disease, flow cytometry.

Received: January 5, 2016

Accepted: January 10, 2016

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