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Change in dosage of Nilotinib

Hi
10 weeks ago my consultant changed me from 600 to 400 mg 2 weeks ago my pcr was 0.022 up from 0.015. I know this is not a change in real terms however the consultant Said the following

"In fact the last two occasions we would have passed it as undetectable (only 1 out of 3 wells positive).

The number of bcr abl molecules was also smaller., only 4 in comparison to 6, so it's an excellent result."

As you see it's an excellent result. But I have never heard the term "wells positive"before. Can anyone explain. Thanks

Hi Steven,

PCR is carried out in a so called "microtiter plate" that has 96, 384 or even 1536 sample wells arranged in a 2:3 rectangular matrix Each sample is put in a "well" (essentially like a small test tube)and multiple samples can be analyzed together.
Usually the analysis of each sample is repeated 3 times and so 3 wells are used - the values of the 3 replicates are then averaged to get the mean result.
In your case only one of the 3 replicates gave a positive results while the other 2 were undetectable - most definitely an excellent result!
I hope this helps to clarify the rather odd term "well positive"

I am also on nilotinib (300mg twice daily)since diagnosis 3 months ago, and I'm waiting for my first PCR results - slightly anxious but trying to think positive. Fingers crossed!

Take care

Luisa

Thanks for an excellent explanation Luisa. I too have had positive results since HH installed their very sensitive PCR methodology/machine last year. I too have been told that only 1 well was positive so not to worry about it. Given that I had an SCT and have had negative results by Q-PCR since early 2006 this was quite a shock to me when they first told me. However, my results are stable and they are monitoring closely. I was told that they have quite a few post SCT patients who only attend clinic every 12 months, that now test positive on the HH machine! I suppose this makes me wonder just what 'cure' means in the context of ever more sensitive technology. I am currently holding BCR/ABL at just about MR5 (0.002%), but I am reassured that it is stable and my 'new' immune system donated by my brother is doing a better job than my 'old' one was.

Steven, I hope the reduced dose suits you better and continues to control your BCR/ABL levels.

Sandy

Thank you.
Having had CML for 9 years I had not heard the term "wells" before.

The explanation is excellent and something that I think I understand. Whatever it is I'm in a good position will my results.
Thanks again.