10 replies to this topic

[Lucas]

hey guys, i had another problem with my pcr. they did a qualitative pcr instead of a qualitative one. I'm in CCYR (don't know my pcr yet due to labs mistakes) and they detected b3a2 breakpoint in the qualitative. can they detect a break point with a low pcr or does it means my pcr is not to low (the lab sensibility is 26 cells in 10e5 normal cells)? thanks in advance. 

[Trey]

It qualitative (instead of quantitative) PCR is only a "yes/no" test for CML.  You cannot tell how low or high. 

[Lucas]

thanks, trey. i think i did not ask the right thing. i just want to know is if they can see the breakpoint, have a identifiable breakpoint in a qualitative if you have a low pcr. like a person in MMR, can they find the breakpoint of the bcr-abl? thanks

[Trey]

If I understand the question, the Qualitative PCR can detect any and all types of BCR-ABL (about 15 breakpoints known to exist), while the Quantitative PCR can only detect up to 3 of them -- it always looks for b2a2 and b3a2, but testing for e1a2 must be requested.

 

The Qualitative PCR is more sensitive than the Quantitative PCR.  But that does not help your particular situation since your are still detectable.

 

Qualitative PCR:

http://www.mayomedic...erpretive/89006

Edited by Trey, 20 February 2015 - 09:54 PM.

[Lucas]

Thanks again, trey. To make my questionar easier, i just want to know if a personagem in MMR can have a detectable qualitative PCR.

[Trey]

Yes.

[Lucas]

trey, i just received my quantitative pcr and it came "below the detection limit" (is it pcru?). I don't know if i can rely on those number and i'll get in touch with the lab to know if they ran my pcr when they did the qualitative or if they ran after with the same sample (maybe this is the reason for the below the detection limit). Is it possible to have a detectable qualitative and a below the detection limit quantitative? thanks in advance.

[Trey]

The lab might have done both types, and the qual PCR is supposedly more sensitive than the quant PCR, so the quant can be PCRU and the qual positive.

 

Most Oncs would not do both at your levels.  You are PCRU by quant PCR, which is what most patients use as the standard.  Good for you.

[Lucas]

thanks again, trey. thanks you so much. they ran a qualitative by mistake. i went to the lab with a quantitative requisition but the attendant selected the qualitative. when i received the result i saw it was a qualitative but at the report they said that they had a quantitative result. i had to get and authorization to get the quantitative report, etc. etc. It was a mess. That was my second pcr on tasigna. my first one got late to the lab - 72 hours  and was 0.043%. hope that's not another mistake because it seems like i'm a very fast responder on tasigna after i was a fat turtle on gleevec.

[gerry]

So are we allowed to congratulate you now Lucas? 

[Lucas]

oh, gerry, i wish. You can congratulate me for my ccyr in 3 and a half months on tasigna

 

Trey, it seems like they did another test with my sample. they will confirm this tomorrow. it's probably not reliable, is it?