Algorithm for monitoring minimal residual disease on the basis of patient-associated immunophenotypes
Yekaterina E. Zueva, Margarita V. Gorchakova, Ekaterina B. Rusanova, Konstantin U. Slobodnyuk
Department of Clinical Laboratory Diagnostics, Center for Laboratory Diagnostics, St. Petersburg Pavlov State Medical University,
St. Petersburg, Russia
Correspondence
Yekaterina E. Zueva, Department of Clinical Laboratory Diagnostics, Center for Laboratory Diagnostics, St. Petersburg Pavlov State Medical University, 6/8, Tolstoy str., St. Petersburg, 199044, Russia
E-mail: yekaterina.zueva@gmail.com
Summary
Aims
Algorithm for monitoring MRD on the basis of patient-associated immunophenotypes.
MRD monitoring aims to identify cells with aberrant or rare phenotypes. It is appropriate to use patient-associated panels for MRD monitoring, which include: (i) phenotypic markers of transformed cells identified at the date of primary diagnostics, and (ii) markers often occurring in a particular variant of AL. Immunological MRD monitoring is an individualized laboratory diagnostic, since individual patients could have a complete preservation of aberrant phenotypes of transformed cells, as well as changes in the expression of some markers.
Methods
A multicolor flow cytometry was used.
Results
Seventy-five cases of primary pediatric AL were studied. Among them were 53 cases of B-ALL, 8 cases of T-ALL, and 13 cases of AML. Monitoring of MRD was performed in 23 B-ALL cases, 6 T-ALL cases, and 5 AML cases.
During MRD monitoring, we observed the complete preservation of phenotypes of transformed cells in 11 cases of B-ALL (48% of cases) and 4 cases of a change in expression (17%). In other cases, MRD of B-ALL was not detected (35%). Complete preservation of phenotypes of transformed cells was observed in 3 cases of T-ALL (50%) and in 3 cases MRD was not identified (50%). Complete preservation of cell phenotypes was observed in 3 cases of AML (60%), while in 2 cases (40%) a change in expression was revealed.
Summary
An algorithm for monitoring MRD on the basis of patient-associated immunophenotypes allows the verification of MRD through the presence of malignant cells with a sensitivity up to 10-5. This algorithm provides full information to clinicians, and thus the possibility to plan transplantations.
Keywords
MRD, flow cytometry, ALL, patient-associated algorithm, monitoring
