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No. of Recommendations: 72
I'll add a couple of thoughts on this already somewhat lengthy thread, since I'm a family doctor who does quite a bit of dermatology.
I am not a dermatologist. And before I heard about it here, I had never heard of DermTech before.

As of now, I don't typically refer to dermatology for pigmented skin lesions that I'm concerned about - I either punch-biopsy them, or completely excise them, myself or if the lesion is in a difficult location for me to excise completely, I refer directly to plastic surgery AFTER a punch biopsy confirms severe atypia or cancer. If the lesion is small enough and/or amenable to a simple excision, I just do that. One procedure and (usually) done.

I would be reluctant to rely on this test to make a clinical decision right now. Here's a few reasons why:

1. Someone mentioned that doctors tend to be slow to change practice. I agree this is quite true, except and until there is clear and convincing and unbiased evidence that the standard of care as it stands should be changed. I don't see that clear evidence for DermTech - yet.

2. Right now, the standard of care for a suspicious, pigmented lesion is to either biopsy a small piece of it or remove it entirely. I think if you asked 100 dermatologists right now: "What's the standard of care for diagnosing malignant melanoma?", all 100 of them would say, "Biopsy". You need tissue.

3. DermTech doesn't change #2 above - what it potentially changes is the number of biopsies you might do in an average week or month. It could potentially save the system money but only if DermTech is specific enough (that is, if it has very, very few false negatives) and fast / easy enough for doctors to adopt in place of biopsy. I would be willing to use DermTech as a screen to decide which lesions to then biopsy, but ONLY if I had high-quality, verified, unbiased data. Right now I don't see that clearly. I didn't dig deep or read everything available, but what I did see is not convincing enough. Maybe they just need to hire more salespeople to convince docs like me.

4. The other consideration is time and money, which to a busy doctor are the same. I would need DermTech to demonstrate why their test is both faster and easier than a simple punch biopsy, which takes about 5 minutes, is practically painless, at worst leaves a tiny (3-4mm diameter) round mark and costs about $200. Most importantly, the biopsy gives you tissue, which at least for now is still THE definitive answer, the standard of care. That's the way I think about it, anyway.

5. From what I have seen on the website and the description of HOW the DermTech test is done in a clinical setting, it looks like it would take about as long as doing a punch biopsy, and costs about the same or even a little more. Yes, if the punch shows cancer, then you need to proceed to a complete excision, but the same is true if the DermTech test comes back positive. I don't think it saves the doctor time. Now, if patients eventually can do it themselves at home, that could be a real game-changer, but can you really trust patients to do the test properly themselves?

My opinion is that this new tool may eventually become widely used and supplant a quick, inexpensive punch biopsy as the diagnostic tool of choice. However, for reasons above, I am not yet sold as an investor or as a doctor.

Family Doc
New Orleans
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