In relation to the blast count, it was quite high at 8% when she was diagnosed back in November. I cannot find any update on the blast count in her further tests. Her BCR/ABL was 97% and then 43% back in March. They also mention 100% Ph (+) in the cytogenic test. I am not sure what this means.
During diagnosis of CML doctors verify number of cells with BCR/ABL gene. This gene is created by translocation of parts of the chromosome 9 and 22. Chromosome 9 is now longer and 22 is short. We have two main techniques to check them.
One is called FISH where we "colour" chromosomes and we can see those who are "short" and "long" This kind of "long" chromosome is called Philadelphia (first time it was seen in lab in Philadelphia, USA). It is done by technician who visually count those changed chromosomes. So he/she take usually 100 or 200 of cells nucleus and count how many of them are with changed chromosomes. So it appear that at your mom's diagnosis all of nucleus taken into account where with Ph+.
Other technique is more precise and it is made by qPCR where at lab they take a sample and multiply/replicate them many times and check expression of that gene. They measure expression of the reference gene (called housekeeping gene). This gene is expressed at constant rate (not only when needed). Usually in CML they use one of ABL, BCR, B2M, GUS. Because techniques, equipment, environment may differ between lab hospitals they make reference to known lab. After that they introduce conversion factor so we can provide result in local lab "units" and standardized "units" they are called IS (International Standard). So in my wife's example at diagnosis she had: 85k BCR/ABL and 119k GUS, BCR/ABL divided by GUS gives 71% and conversion factor is Cf=1.6. 71%*1.6 gives 115% IS. Because it is measured against other gene expression and because of Cf result can be more then 100%.
CML is defined with 3 phases: chronic, accelerated, blast. Besides number of white blood cells, platelets we measure no. of blasts. During normal blood cell life cycle blast differentiate into different types. Because of CML they are not. Instead of normal blood cells patient get only blasts. Chronic phase is below 10%, accelerated 10-20%, blast more then 20%.
At which hospital your mom is treated?
Best regards / Chris
IS is of course International Scale not Standard.
David posted link to a document with better explanation here: https://cmlsupport.org.uk/thread/13195/quick-question-bcr-abl-numbers#po...