The measurement of minimal residual disease (MRD) populations is often performed following treatment for leukaemic disorders. The levels of MRD are used as a predictive factor for relapse and as an indicator for patients entering remission. As such the measurement of MRD can have a direct effect on the treatment regimen of a patient.
This programme issues stabilised whole blood into which has been spiked some stabilised B-ALL material. Laboratories are required to determine the level of minimal residual disease by flow cytometry, please note this programme is not suitable for the measurement of MRD by molecular methods.
The programme issues a presentation sample together with 2 follow up samples. Please note that the presentation sample will not contain the expected level of disease seen in a typical clinical scenario. The 2 follow up samples are manufactured from the same B-ALL case and are designed to represent different stages post treatment to assess the ability of a centre to detect B-ALL leukaemic cells at minimal residual disease levels within a background of stabilised normal whole blood. Laboratories are requested to report the percentage of residual leukaemic cells in the 2 follow up samples as a percentage of the total leucocytes.
Three samples are issued per trial and this programme issues samples a minimum of 2 times per annum and a maximum of 4.
No activities in relation to this EQA programme are subcontracted.
As a result of an internal review we have taken the decision to adjust the performance monitoring limits for quantitative programmes.
• A result between 2.5 and -2.5 will now be classed as satisfactory
• A result between >2.5 and 3.5 or <-2.5 and -3.5 will be classed as an 'Action’ result, which highlights a potential issue to the laboratory. Two ‘Action’ results in a period of 3 samples would result in classification as a ‘Critical’
• A result above 3.5 or below -3.5 is considered to be a ‘critical’ result requiring immediate investigation by the laboratory