4 replies to this topic

[cometbro]

So it was my 3 month mark last month and I sent an email to the physician about a week after getting blood drawn.  I asked if i'm getting a PCR and she said that she went to get this tested on my blood at that time.  I asked by email what were the results and she said, "congratulations!, you've reached MMR".

So I get all excited and start posting about what is the fastest CMR ever..etc..  I just went this month and this time I asked for a hard-copy of the PCR.  When I go home to look at it, it says this:

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BCR-ABL/GUSB

Current specimen:   2.73 x 10 - 3  (0.273%)

First positive specimen (MP10-1195, October 2010) :    4.02 x 10 - 2

Log decrease relative to the first positive specimen:   1.17

____________________________________________________________

I said, WHAT!  This is not MMR, I thought MMR was a 3 log reduction, not a 1.17 reducition.  I emailed her telling her that I thought an MMR was a 3 log reduction.  She emailed back "Yes you are correct about 3 log reduction, but you started off fairly low tumor burden.  Most people may have a 10 to +1 and you had a -1.  We call MMR anything below 10 - 3"      (10 - 3 ; same as 10 ^ -3; same as 10 to the negative 3).

Just when I thought I was understanding it, I see this and it confuses me more.  I don't even know what tumor burden is.  My mindset from reading everywhere is that you have to have a 3 log reduction in order to reach MMR.

I just emailed her back and asked if I'm progressing as I should be and she said, absolutely.  I'm hoping she's just not trying to make me feel better.

Can any body shed some light if this is truly MMR, also on what is tumor burden, and also how this tumor burden could be -1 if my WBC at that time was around 200,000.  Thanks.

[Trey]

You seem to be doing well, so keep that in mind.  PCR confusion is not news to any of us here.

Oncs can use either personal log reductions or "lab standard" log reductions.  Yours is saying that you are close to achieving a roughly 3 log reduction per the lab standard.  For International Scale, that standard is .1% for a 3 log reduction/MMR, so it sounds like your lab is on International Scale PCRs.  But your personal progress from your individual first PCR is just over 1 log reduction.  It is fine to use lab standard log reductions, even though it is not exactly equivalent to personal progress since you feel like you were spotted a head start.  The MMR goal is not an exact measurement, but a rough approximation of what is considered very good progress.

Your Onc said that anything 10 to the -3 is MMR, but I would say that 9 x 10 to the -3 is not MMR, although 1 x 10 to the -3 is close (if on International Scale).

"Tumor burden" is roughly defined as the percentage of leukemic WBCs in the blood.  In a sense, leukemia is a diffused tumor.

I wrote an article for a publication about PCR confusion:

http://www.cancernet...e/10165/1570782

[cometbro]

Hey Trey, appreciate the response, thanks.  I feel better with that explanation and will keep in mind what you said in the article about PCR results are best used when viewed over time.  When she said MMR I got too excited and was jumping the gun without even looking/trying to analyze the results myself.  I'm glad I seem to be doing well and will just have to have patience...*think lifestyle* with the medicine and not burden.

[PhilB]

Hi Cometbro,

As Trey has said, the important fact is that you are doing really well.  It's only a relatively minor issue that your onc appears to have failed Mathematics 101.  On the IS MMR is defined as 0.1% (or 10 to the -3 for those who want to try to confuse people.  Doctors do this to try to make themselves look clever - in just the same way that they translate your symptoms into latin and give it back to you as a diagnosis)  Your score of 0.273% is a 2.56 log reduction against the lab standard.  The last time I checked 2.56 was less than 3.

Boiling it down to the essentials:

Have you reached MMR per your last test?  I'm afraid not.

Have you got a really excellent result for someone only 3 months in?  Most definitely.  Put on your dancing trousers.

[cometbro]

Hey PhilB, thanks for the response.  I will put on my dancing trousers, hahah.  I guess its partly my fault because i'm very relaxed about asking for the hard-copy.  These people are so busy (Cornell / NY Presbyterian) and are just pumping people in and out.  Not to mention that I'm desperately trying to get out as fast as I can.  There's always so many people there and every time I go, i'm like the youngest one there waiting.  My doctor is probably the most well known doctor there for this and most of the times I don't even get to see him.  He has his "assistant" see me.  I just usually go in there, am asked how I'm doing, and i'm out.  I'd prefer just emailing anyway.

I'm definitely glad for this message board and you guys.  I would've never asked about PCRs,MMRs and such things if it wasn't for me reading it over here.  Thanks.