Tuesday, July 17, 2007

New Breast Cancer Molecular Diagnostic

The Cancer Genetics blog has a post on the approval of Veridex's new RT-PCR test for breast cancer spread.

What was emphasized in the Globe article which is striking is that this test can potentially be performed while the patient is still on the operating table, avoiding a delay between screening test & initiating follow-up testing. If this holds true, then this is an example of molecular diagnostics really having a big impact in a major health problem. As with any diagnostic test, the key question is specificity & sensitivity aka false positives and false negatives. The key study had 300ish patients in it, which is just a small puddle compared to the ocean of breast cancer patients.

Veridex, which is owned by J&J, has some other cool technologies cooking, including some to sift tiny numbers of cancer cells from the bloodstream, cells which have escaped from the primary tumor or metastases. Since getting clinical samples can be a serious challenge, this technology is pretty amazing.

7 comments:

  1. Saw this earlier today and forwarded it to everyone at work. Fascinating stuff

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  2. sure - it's amazing approach, just covered recently in my post: http://cancergenetics.wordpress.com/2007/07/18/johnson-johnson-genetic-testing-fda-approved/

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  3. Apologies, I mangled the name of your blog -- your post was the reminder I wanted to comment on this.

    I've edited the entry to attempt to fix the error.

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  4. Without some data on sensitivity and specificity it is impossible to evaluate: if the test detects 50% of true positives (sensitivity 50%) and 50% of true negatives (specificity 50%) then it is not very valuable for the clinic. Imagine crapshoot that hits the target 50% and drags mets-negative person into a nightmare of apprehension!

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  5. The Boston Globe article put the true positive rate at 88% and the true negative rate at 94% -- not shabby, but apparently not quite as good as the sentinal lymph node biopsy it is attempting to replace.

    There are some widely used screening tests with horrendous false positive rates; the AFP-based pre-natal screening for Down's & spinal bifida will be horribly familiar to anyone who has reproduced in the last decade or so.

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  6. thats fine - thanks. just published new post about evidence based oncogenetic diagnostics: http://cancergenetics.wordpress.com/2007/07/20/evidence-based-genetic-testing-breast-cancer/

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  7. Your article was nice. Friends of Faith is a nonprofit organization founded by the late television news personality Faith Fancher of KTVU. Event to be held at the Palace of Fine Arts on Monday, March 29th 2010 at 6pm. For Details http://www.xumri.com/friends_of_faith.php

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