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Fluctuating Log Reduction results

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Hi All,

New to this forum, but a quick note about me. I was diagnosed with CML in December of 2016. Since then, I've been on a daily dose of Sprycel 100mg.

In addition to the monthly checkup to receive my prescription, my doctor does a PCR once every 3 months. In September 2017, my Log Reduction was down to 3.2...but then in my December 2017 results, the results went back to Log-2.8. I just wanted everybody's 2-cents on whether this is something to be alarmed about.

In addition, how has everyone else faired (under which treatment) in the first year of your treatment? Did you manage to achieve MMR or CMR?

Hi. There are others who know more about this than I do, but my feeling is that I wouldn't worry about this. The difference is from memory within the accuracy range of the testing process, so the actual results may still be trending in the right direction. Log 3 reduction is not a bad place to be. Hopefully your next test will show the trend going back down - if not it may be time for your consultant to have a think, but not yet

Hi there!

I'd echo Alastair's response. There can be a great deal of fluctuation between PCR tests, even from the same lab. One important part is the number of assays - more than 100,000 is the gold standard, but sometimes this can't be reached if the blood sample is a bit old ,and various other operational reasons. So a test which had 33,000 assays would be 3x less sensitive than one with 100,000. In this situation, variances can be magnified a bit.

But let's come back to your results.

A 3.2 log reduction put you somewhere in the realm of one cell in about 12,000 (forgive my rough maths), and a 2.8 log reduction is more like one cell in 8,000. Not an enormous difference when all is said and done, and fluctuations are definitely to be expected. In any case, the time to question rises is probably after 3 sequential ones (unless the change is very significant).

For what it's worth, after a year I was at about 0.131% which is not dissimilar to your 2.8 log reduction. I'm now at 0.004% (pending latest results) a few years later.

David.

Hi David & Alastair,

Thanks for your responses, that definitely reassures me that I'm not an anomaly. My doctor did mention to me that I really should try to adjust my sleeping schedule so I'm not sleeping from 12/1 AM.

Lastly, if anybody has a suggestion on good websites to learn more about calculations, that would be greatly appreciated. I'm living in Taiwan, so it seems that the results that I get are only limited to log reductions, not so much assays, or % count.

 

Cheers

Hi. as david and alastair said, blips are very common. PCR tests are very, very sensible and they have a big margin of error (half log). You're in a nice place for a year in therapy. Just follow the trend. Good luck! 

I would say the best place to learn about PCR tests is from our very own booklet :-)

You can find it by going to "News", then "Our Publications", then click on the first link titled "Quantitative Reverse Transcription Polymerase Chain Reaction: A primer for patients".

Here's the direct link to the booklet: https://www.cmlsupport.org.uk/sites/default/files/qrt-pcr-primer.pdf

This booklet was published by this web site, in conjunction with CML specialists from the NHS here in the UK, so you can trust what it says. It does go into a lot of detail, but is suitable for all levels of CML knowledge.

David. 

These are my results. My tests are done in a lab in New Jersey, USA.

7 April 2017  date of dx
BCR/ABL1 of b3a2 Type: 59.08%  International Scale Ratio: 49.0364%


6 July 2017  3 mos. post dx
BCR/ABL1 of b3a2 Type: 6.82%  International Scale Ratio:  5.6606%


28 September 2017  6 mos. post dx
BCR/ABL1 of b3a2 Type: 0.60%  International Scale Ratio: 0.498%


21 December 2017  9 mos. post dx
BCR/ABL of b3a2 Type: 0.16% International Scale Ratio: 0.368%

No MMR yet at 9 months but the trend is good, I think. Don't know how this translates to log reduction.

Thanks for the information pamphlet David!

Justine, that’s roughly the same trend I followed in the first year. It does look like you’re heading on a good recovery trend!!:) 

Hello there,

My diagnosis was also in December 2016, with CML % count so high that even the lab commented: "unable to provide accurate number". Let's not talk about my white blood counts!

Funny, even with all those jam-packed CML cells and off-the-roof white blood tallies, the only actual symptom i had of the disease was a splenomegaly.

Thankfully, those dark moments of my life are now far behind me.

Above said, i never once want to forget that faithful day back in Dec 2016. In fact, i now celebrate my birthday on the day of my CML diagnosis as it marks another year of survivorship and a personal reminder that CML is here to stay. Sad, huh? Not for me, because i don't want to continue to see CML as an illness that translates into mental weakness and doubts. Hence, i choose to see it as a rebirth of my life after a life-changing trauma. Besides, way i see it; for me to get better, i have little choice but to quickly and fully accept what is happening to me.

All right, enough with the back story of my life!

To some details on my treatment therapy and response's rate; I'm currently on nilotinib/ Tasigna 300mg twice daily. Not the same class of drug potency as your dasatinib/ Sprycel, but my PCR tests yielded enough satisfactory results to be contented in the last 12 months - according to my hematologist.

My PCR IS results:

Day0- Highly remarkable
Day29 - 38%
3Month - 0.98%
6Month - 0.059%
9Month - 0.039%
12Month - 0.032%

Commentary to my 9th to 12th PCR - not so glamorous compared with my former ones which i speculate has a lot to do with the reappearance of my hyperthyroidism. The latter has caused all sorts of havoc to my sleeping and digestion patterns while it lasted. Now with my TSH level normalized again, i hope to see some much-desired improvement to my PCR reading in two months time! Either or all, these days I am no longer bothered by the slight fluctuations in my PCR results' trend. WHAT for? As long as i continue to feel great, live well whilst doing everything right within my willpower in the management of my CML (i.e., TKI adherence, balanced diet and exercise) and still enjoying all the best things in life with my loved ones, then nothing else mattered. Or at least, until my hematologist started to voice his concerns over the results, I decide not to waste my precious time of my day/night worrying about it!

More over, back to your post- i can definitely relate with your 12Month journey and i also think your doctor might be on to something when he implicated irregular sleep patterns may be affecting your overall result. I.e. lack of sleep may affect the body's TKI absorption and release etc,.

Wishing you all the best with your CML journey.

Best Regards,
Ellie.

I neglected to mention that I have been on 400 mg Gleevec since day 1.

Take care!