Apr 12 2012

Cutting Edge Cancer Diagnosis: Circulating Tumor Cells

This year’s AACR annual meeting focused a great deal on the vindication of a very old idea:  “seed and soil” model of metastasis.  The idea that little seed cells from a tumor circulate through the body looking for fertile ground to implant into and grow a metastatic tumor.  It’s only very recently that the technology has existed to provide a mechanism to detect these circulating seed cells.  This knowledge has proven to be very important in predicting which patients will respond to different therapies.

This video is taken from the only FDA approved technology to detect these circulating tumor cells (CTCs).  For any of you interested in what I do for a living, this is the clinical outcome of some technologies that I worked on at the “research use only” non-clinical level.  Being able to tag cells with magnetic particles or beads and separate or enrich from that binding.

It’s five minutes long and includes a commercial in the middle, but I thought it was a cool “infographic” format.  Very CSI!

83 comments on “Cutting Edge Cancer Diagnosis: Circulating Tumor Cells”

  70. Your current report features proven helpful to me.
    It’s very helpful and you’re clearly extremely experienced in this region. You have exposed my sight to be able to different views on this kind of subject matter together with intriquing, notable and reliable articles.

    Reply

  71. Would you consider to do a video about Turmeric Curcumin? Richard Dawkins, just posted a radio interview about it on his youtube channel. It sounds too good to be true. As a former student of biochemistry, it seems a unlikely to me that one chemical can have that many BENEFICIAL effects. If there was a quick fix, wouldn’t evolution have figure that out a few million years ago? Make the body produce the chemical, or learn to yearn the spice as if it was sugar. But hey, back then people died earlier and from other causes than cancer et.c.

    Thanks in advance, and thanks a lot for your compassion to communicating scientific research to the public!

    Reply

  72. Quite a shame I did not know you were attending AACR! As a fellow scientist, I would love to have personally thanked you for all the great videos you make.
    Cheers,
    M

    Reply

  73. I suggest that you read about this subject on the famous blog “science based medicine”. The authors analyses every claim by the view of science and discuss the use of the method in real world

    Reply

    • I read SBM on a regular basis, but I don’t know that they have ever covered CTCs and the seed and soil hypothesis. It’s solid science, albeit a frontier topic where much stands to change on the evidence.

      Reply

      • A quick question about this. Isn’t the epithelial cell adhesion molecule and cytokeratin also found on endothelial cells? How then is this test specific for tumor cells? It seems to me whenever endothelial cells are shed into the blood stream, i.e. in patient sufering from atherosclerosis, or endothelial inflammation, or just normal shedding, they would be detected as tumor cells. Also wouldn’t this test only detect cancer cells of epithelial origin, or those expressing epitelial specific proteins? In other words it would only detect squamous cell carcinomas. Lasylu, aren’t most metastatic cancers mostly anaplastic and dedifferentiated, therefore wouldn’t express tissue specific antigens?
        Is there solid science, i.e. large scale studies, to back this up

        Reply

        • These are great questions for a different format. You can read more about EpCAM (epithelial cell adhesion molecule) in the primary literature. Start here:

          Cell Mol Life Sci. 2011 Dec;68(24):4009-22.
          “Lessons from common markers of tumor-initiating cells in solid cancers.”

          Curr Mol Med. 2008 Dec;8(8):784-804.
          “CD44 and EpCAM: cancer-initiating cell markers.”

          The short, blog-friendly version of the answer is that this test has a good positive
          predictive value (PPV) because it focuses on a very common marker on metastatic breast cancer. This marker, in fact, is expressed primarily on de-differentiated cells that are likely to be found on CTCs of this type. There are populations of cells that could be false-positive for both markers, and there are CTCs that could be false negative for both.

          As the technology progresses, I’m sure we will see more variety in the types of clinical panels in use on the same technology.

        • Specifically, I would be interested in knowing whether the predictive value of circulating tumor cell assay is based entirely on identifying patients with non-malignant epithelial or endothelial cells, such as atherosclerosis (worse survival but not because of the cancer) and endothelial dysfunction, for instance vascular trauma from a biopsy or tumor excision of a lesion which was already deemed more malignant based on imaging, histology, etc.. In other words, the predictive value of the CTC could entirely be a by-product of more invasive excision/surgery for more agressive tumors.

      • Ah ok, got that. But don’t you think a patient with for instance a histologically more agressive cancer (anaplasia, dedifferentiation, expressing EpCam) would be subjected to radical axillary lymph node resection, masctectomy, etc…. as opposed to a patient with a histologically less agressive tumor? Don’t you think then that the patient undergoing more radical surgery would have more circulating epithelial cells expressing (even expressing EpCam because the resection is near the tumor) just due to to vascular dysfunction? If so, wouldn’t the PPV of the assay be entirely dependent on the prior identification of agressive tumor based on histology? HAs this even been examined in research?

        Reply

    • Have you checked to make sure you’re not blocking c0nc0rdance.com, wp.com and videopress.com? The video works as of the time of this post. Actually if you block scripts from c0nc0rdance.com you’ll see a link to the video on the videopress website. You can follow that to the video.

      Reply

      • It’s good now, I’m got in real quick after it was posted – so maybe it was fixed or just randomly didn’t show up. Thanks though!

        Reply

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