Re: R & the rest of the group - M

[Guest guest]

Hi ,

> Date: Wed, 16 Mar 2005 16:49:23 -0500

> From: " ez " <lmartinez@...>

> Subject: R & the rest of the group

> Saw your post the other day about some changes in your PCR test and hope you

> are doing well.

Thanks for your concern regarding my PCR. I still don't know whether the

increase from a very low 0.0002 to 0.0018 was real or not, because the

repeat test had a sensitivity of only 0.002, as opposed to their usual

0.0001. I don't know why this is; I was told it's because my RNA might have

degraded, but this doesn't really make much sense to me. In any case, I've

stopped worrying about it because the chances that I'm actually relapsing

arre very low, and I've got much better things to think about. I am,

however, considering switching centers for future PCR's. Boston is much

closer to me than NYC, and MSKCC's lab has been just a bit too disorganized

for my taste. I'd appreciate recommendations from any of you regarding Dana

Farber heme-oncs.

> In February 2004 my BMA indicated that there was a very small amount detected

> In one of the 3 major break points. .1 very low. But with that my doctor

> insisted I go and get another PB PCR and see if it was the same or if it

> differed. So I went back to my local Cancer center here after almost 4 years

> of not going there and their test was negative. We decided to believe the

> best. I was scheduled for this years BMBA just this Monday and prior to my

> visit my Dr asked me to go get my PCR at a different lab (Labcorp) My results

> from Labcorp indicate the same major breakpoint from last year going from .1

> to .5 and now another one of the 3 is .22 It is a small amount I know but

> again we are thinking about the possibility of an upward trend. We are now

> going to compare the PB PCR to the BMA but the results won't be In until

> around the end of next week. To go one step further my doctor has me going

> back to the local center here to use their Lab so we can compare all 3. I

> think he still believes that there is a difference in the PB PCR test and The

> PCR from the BMA.

>

> My question is how the heck do we know which darn lab has accurate results?

> And is it really safe to go a whole year without a BMB? I dunno???

> As soon as I get my BMBA results I will post it all here so we can all try

> to figure out what's going on.

I agree, this is all pretty confusing, . It's a common dilemma -

getting second or third opinions, or backup lab tests, then not knowing

which to believe among the differing results. It doesn't help that qPCR's

for BCR-ABL haven't yet been standardized nationwide. This pertains to the

problems I'm facing as well.

A couple of questions about your post. First, I'm unclear on whether the

breakpoint that was noted in your test was the same as the one you were

diagnosed with, or a new one. That is, was the 0.1 a ratio of one breakpoint

to another, or is that the actual qPCR result? I'm a bit rusty on the

subject of breakpoints, but as I recall, a couple of them carry normal

prognostic significance, where others are not so favorable.

Then there's the matter of PB vs BMA. With respect to breakpoints, I don't

think it should matter which one you use because within a short time of

being produced in the marrow, all white cells show up in the blood. It's

only when the Phillies are reproducing rapidly, such as in accelerated or

blast phase disease, that there's likely to be much of a discrepancy. There

are other reasons to have BMA's done from time to time though, and if you

haven't had one for over a year and have still not reached a 3 log reduction

by qPCR, then I'd consider it a good idea.

I look forward to seeing your next test results.

Warmly,

R