At the moment probably not, but in the future we could expect some changes. Whereas in the previous 2006 and 2009 editions, the ELN recommendations for CML treatment and monitoring were indicating the cytogenetics analysis as the main method to evaluate the response to TKI treatment of CML patients at early times points (3 and 6 months), the 2013 edition recently published suggests that a strict molecular monitoring at these time points is also highly recommended and to be performed with a standardized method of RQ PCR. This is a consequence of a number of studies that have provided evidence that a BCR-ABL level above 10% at 3 months or above 1% at 6 months is predictive of an inferior outcome in terms of PFS and of OS with a statistical significance and more predictive of a corresponding achievement of a PCyR response at 3 months or of a CCyR response at 6 months.
A) Within this context, the labs are expected to focus their efforts to standardize with great precision the detection of these levels of BCR-ABL in addition to MMR, that according to ELN 2013 recommendations still remains a step to be achieved within 12 months in order to have an optimal response. This would probably be more probably achieved using the Cepheid machine, that could indeed present several advantages with respect to the more traditional methods, like an decreased need of sample exchanges to establish the conversion factor of an individual lab and a more rapid availability of the results of the analysis, because the entire process requires only 2-3 hours. The latter is a important aspect to be considered, because the BCR-ABL level at 3 or 6 months is expected to be the basis to drive a possible change in the therapy.
B) On the other side, a great deal of attention has been recently focused of the precise definition of minimal amounts of residual disease (MR4, MR4.5 and MR5) as this could represent the basis to enroll the patients in trial leading the CML patients to treatment discontinuation. This could be ideally achieved with new methods of digital PCR, that do not need a control gene (and therefore no need of standardization) and could detect the residual copies of BCR-ABL transcripts with great precision.