6 replies to this topic

[snowbear]

I just had my first 3 month PCR test.  At diagnosis, it was 22.5%; now, it is at 19.5%.  Being the my white blood cell counts improved so dramatically, so quickly, it surprised me that my PCR is still so high.

 

Doc says as long as it's moving in the right (down) direction, she's happy.

 

Is this pretty typical progress for CML ?

 

edit to add:  I take Gleevec 400 mg

[Gail's]

My dr explained that people have different rates of resolving. I was 37% 2 months ago, now 15% but dr cautioned not to expect that decline to continue so quickly. She said they don't worry unless it takes a year to reach undetectable.

[Trey]

I prefer to see FISH results until CCyR.  PCR at the higher levels (above 10%) is unreliable. 

[chrissy778]

Undetectable in a year that's quite the expectation, Geeez

[snowbear]

Doc didn't order a new FISH test.  That was in the 90's at diagnosis which I don't understand since my BCR-ABL was only 22.5%.   If 90% + of my WBC are abnormal (Ph+), then wouldn't they ALL contain the BCR-ABL gene?

[Trey]

FISH and BMB both measure actual cells, PCR is an estimator which only uses cell DNA fragments compared to other cell DNA fragments, and there can be multiples of each per cell.  At "higher" levels (above 10 or so) PCR is not very accurate.  Using International Standard a person can have a PCR well above 100%, which shows it is not based on leukemic cell counts.  So a PCR percentage does not relate to percentage of leukemic cells in the blood, just percentage of BCR-ABL genes compared to other genes.

[snowbear]

Thanks, Trey.  I understand the basics of CML, but the nitty gritty details still over my head.  I came across a post by you about Cytogenics earlier today and it was very helpful in understanding how CML develops and why it's still not curable.  Thank you!!