Very interesting , good information . The first time pcr explain like that . Thank you very much . Emile no 527 Zavie's Club
-----Message d'origine----- From: peg Sent: Tuesday, May 31, 2011 2:54 PM To: CMLHope Subject: [CMLHope] PCR BCR-ABL Results
Friends, I do not post very often here any more, ever since I discovered that when my name, e-mail address, etc is google searched, all my posts here, that I thought were private, are revealed to the world, possibly outing me to those I would not choose to give personal info to, such as business associates. I do still monitor the site though and will often respond privately to old friends. However, a recent posting regarding PCR BCR-ABL testing caught my attention and seemed important enough to address to all. PCR's are affected by many variables, including but not limited to labs holding blood samples too long before processing. RNA, which is what the PCR looks at in the blood, has a lability problem, and degrades within hours of the draw. It can genderally cause an erroneous low reading at anything past 36-48 hours. Everyone agrees that the best results will be on blood used within 24-36 hours of the time it is drawn. However, many labs will hold the blood far longer that 36 hours, sometimes up to 72 before processing. While this is alright with some testing, it is not with PCR's! Once the RNA degrades you will get a false low reading, even a false zero/PCRU. I am sharing this because it is important to understand that if you get a PCR that is low (or zero) and the next one is elevated again...this may mean absolutely nothing, if the low PCR was an erroneous low! Here is what is important to remember: 1) You should pick one lab and stick with it, since interpretation and protocol will vary from one lab to the next. 2) You should never get your blood drawn on a day, such as a Friday, when it will not be able to be tested the next day (unless your lab runs PCR's on Sat.). 3) You should verify that your lab does not save cost by holding samples until they have many from many patients. It is better to know what day the lab actually does PCR's and have your blood drawn the day before. 4) You should always inquire what date and time the PCR was actually run, and not just the draw date and reporting date. If it is greater that 36 hours after the draw it is probably inaccurate, the greater the time, the greater the inaccuracy. 5) MOST IMPORTANT - Do not consider any one PCR valid...but rather look at the results of two consecutive ones, if you have two that are both trending downward, this is good, if you have two that are trending upward, maybe bad. An extreme low in the middle of a downward trend, then one that is higher (but still the same or lower than two PCR's ago) does not necessarily mean that you have lost therapy control, it could simply mean that the extreme low was erroneous. Unless you are in blast crisis nothing is going to change quickly, so don't panic. This is the time to take a deep breath and wait for the next PCR, which may show that you are still trending in a good direction, if you take the one erroneous low out of the equation. This type of error happens more often that doctors and patients realize, and often pushes people into hasty and needless changes in therapy. I know, it happened to me! Because of that I did a lot of research, consulted with smart people, and picked a new lab that runs it within 24 hours. Hope this helps ease some minds and arm everyone with some good info. Remember, if CML is the bus, you are still the driver and you should expect your docs to help navagate, not drive! Knowledge is the key! Keep the faith, peg -- [CMLHope] A support group of http://cmlhope.com ------------------------------------------------- You received this message because you are subscribed to the Google Groups "CMLHope" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/CMLHope
