4 replies to this topic

[Asmaa]

I have been on tasigna for 1 full year from diagnosis and just got my BMB results.  I noticed everyone else putting their numbers in percentages and log reductions but what my doctor mailed me does not put the results like that.  was hoping someone can tell me how to convert the numbers or at least understand them.  I pretty much get that I am not pcru due to the detection of cancer cells. but i'll just put what my doc wrote below.

"Your BCR-ABL PCR was + in 218 cells from peripheral blood and 40 cells from bone marrow, both down from 535 positive cells in February (which in Feb.I only had blood tests, no BMB). FIsH on your bone marrow was normal in 100% cells examined"

I don't really know how that translates into if i'm "on track" or not, and what is fish?  sorry so ignorant,  i'm a very busy mom, haven't done my research in CML vocabulary or test result translation.

thx for any light you can shed, i appreciate it.

[PhilB]

Hi Asmaa,

Those PCR numbers aren't hugely meaningful as they stand - I would suggest you call your doctor for more clarification.  What the PCR measures is the ratio of how many BCR-ABLs they find to the number of control genes they counted.  If they found 535 BCR-ABl in Feb against 10,000 controls and 218 now against 10,000 controls then your numbers have improved.  If, on the other hand the new number is 218 against 2,000 controls then the proportion of positives is higher.  To really know what's going on you need to look at the ratio of BCR/ABL to control in both cases so that's the further info I'd be trying to get from the doctor.  If your doctor doesn't understand this (which is not that uncommon I'm afraid) then ask him for a copy of the actual test results and post them here - where there are plenty of people who do know how to read a PCR test and will be happy to oblige!

Having said the above, I don't think the fact that your doctor may be a bit dopey is a reason to get too worried at this stage as you do appear to be doing well.  The FISH test looks at 200 to 500 cells to see if any of them are Ph+ (Stick the cells in with a couple of chemical dyes, one which binds to BCR, one to ABL.  One dye is red the other is yellow.  Look down a microscope and if you see anything orange then that's a BCR-ABL).  It's less sensitive than PCR, but much more sensitive than standard bone marrow cytology.  Yours is zero which means that as a minimum you have a good, solid complete cytological response.

All the best

Phil

[Asmaa]

ok thx.  I called and the nurse was able to tell me that the BCR-ABL that was positive in the blood for 218 cells, was out of 100,000.  At diagnosis, I remember having a positive of 33,000 which I assume was also out of 100,000 since the control number was the same for February as well (535/100,000) so it seems that's the same control they always use.  And the bone marrow is the same ratio with 40/100,000 positive.

now the questions...

So is this good, and on target for the 1 year marker, even though it's not PCRU?

and if this is translated into a percentage, is that what it means when other people post their numbers as .002 % or whatever?

and is my log reduction mean how many places the decimal moves when you translate it into a percentage?

what is the difference between Ph+ chromosomes being detected, and BCR-ABL being detected or is it the same thing?

and what is the point of the FISH if you are having a more sensitive test done anyway?

trying to figure this all out, and what the numbers mean.  thanks again for any help.

also waiting on a call from the doctor,  are there any other questions I should ask? 

[Trey]

218 leukemic cells out of 100,000:

PCR percentage is calculated as:

218 divided by 100,000 = .00218 (ratio)  times 100 = .218% (percentage).  The percentage is the value that is used for tracking.

Log reduction depends on the lab.  If International Scale (IS), you are close to the 2 log reduction number which is .1%   If IS, this is roughly equivalent to CCyR, which is the goal for 12 - 18 months.  CCyR at 12 months is good.  CCyR at 18 months is the minimum goal for acceptable response to TKI drug treatment.

[Asmaa]

ok thanks.  now within what time frame do people normally reach PCRU?  I thought they expect it by 1 year, no?