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Latest set of results

Hi all, been on Imatinib since October 2011, had my latest result today

"Your bcrabl/abl1 ratio from the last appointment is 0.006. This isn’t quite a 3 log reduction yet but is a continuing decrease in PCR transcripts. Hopefully there will be a further decrease when we next check it."

Now i thought i understood these figures but doesn't this put me at over MMR4 ? Emailed Doctor I saw, and now emailed back saying

The cytogenetics laboratory reports the PCR in a few different ways. The scoring you are referring to is the bcr-abl/abl % - and the number I gave you was the bcr-abl/abl ratio.
I think the most standard measurement is the bcr-abl/abl% and I'm sorry if I have confused you with the different measurement.
Your bcr-abl/abl% is 0.6% which remains an improvement on your previous result from late 2012 but hasn't quite reached MMR yet, which you quite rightly have defined as 0.1%.
The other results I gave you were bcr-abl/abl ratio and can be easily converted to the international bcr-abl/abl% scale by multiplying them by 100.

Is this right you multiply by 100 ? Any help would be great.

All the best to all. Nigel

I have tried to find an explanation that would help but, as you can see from the snip from an article published in Blood (2006) by Tim Hughes..see below... I find your doctors explanation confusing too. I thought the percentage reflects the ratio of BCR-ABL gene copies to the control gene copies (in your case ABL is the control gene), but it is highly complex and in order to stop driving yourself mad it is probably best if you take his advice and use the percentage figure he gave you... 0.6% BCR-ABL/ABL ... as that is the kind of result you have been given previously so it is best to compare apples with apples.

best wishes, Sandy

Not sure if this is helpful but here goes.

"....The results in an individual patient should ideally be expressed as a
percentage reflecting the ratio of BCR-ABL transcript copies to
control copies. Of great importance was the suggestion that individual laboratories could derive a conversion factor that would enable them to convert their own results to an international standard."

In order to convert a given local result to the international scale, it is necessary to use a conversion factor (CF). Examples from 3 labs (The London conversion factor is 2.22)

CF 0.1% divided by MMR Eq (since 0.1% is the agreed value for MMR on the IS)
Once a laboratory-specific conversion factor has been derived, it can be used to
convert all local values to the international scale (IS).

The use of prepared material will eventually allow each laboratory to determine a BCR-ABL/control gene ratio as a percentage equivalent to a MMR RQ-PCR FOR BCR-ABLTRANSCRIPTS as established in the IRIS trial. The conversion factor (CF) for each laboratory is then linked to this value. The BCR-ABL values are multiplied by the CF to convert to the international scale and expressed as BCR-ABL values on the international scale. The process for conversion is illustrated in Table 1 using the MMR values that have already been established in 3 laboratories, and the suggested format for reporting is shown in Figure 1."

see page 32
http://bloodjournal.hematologylibrary.org/content/108/1/28.full.pdf

Thanks Sandy thats a great help, will email the Doctor to see if she is able to find out the conversion factor used in Birmingham.
All the best Nigel