Researchers have developed a way using lasers outside the skin to detect and destroy melanoma cancer cells spreading through the blood. The method is ~1000x more sensitive than current detection methods which require drawing blood.
This approach monitors the entire blood supply of the patient for cancer cells, where current methods examine only a few milliliters which may not contain melanoma cells even if they are circulating.
The new technology, dubbed the Cytophone, uses pulses of laser light on the outside of the skin to heat up cells in the blood. But the laser only heats up melanoma cells — not healthy cells — because these cells carry a dark pigment called melanin, which absorbs the light. The Cytophone then uses an ultrasound technique to detect the teensy, tiny waves emitted by this heating effect.
Researchers have tested the technology on over two dozen light-skinned patients (dark skinned individuals have lower incidence of melanoma) and successfully identified circulating tumor cells 96% of the time with no false positives.
[T]he team also found that after the treatment, the cancer patients had fewer circulating tumor cells. "We used a relatively low energy" with the primary purpose of diagnosing rather than treating the cancer, Zharov said. Yet, even at that low energy, the laser beam seemed able to destroy the cancer cells.
Here's how it works: As the melanin absorbs the heat, the water around the melanin inside the cells begins to evaporate, producing a bubble that expands and collapses, mechanically destroying the cell, Zharov said.
The researchers have also demonstrated the ability in the lab to target breast cancer cells which do not carry melanin by using a marker that binds to those cells.
Most cancer deaths occur due to metastases from the initial tumor to vital organs as a result of circulating tumor cells spreading. Reducing or halting metastasis has significant therapeutic potential.
Journal Reference
In vivo liquid biopsy using Cytophone platform for photoacoustic detection of circulating tumor cells in patients with melanoma
(Score: 1) by RandomFactor on Sunday June 16 2019, @01:52AM (5 children)
Why not toast the original tumor while you are at it? (and yeah, I know that's not begging the question)
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(Score: 3, Interesting) by RS3 on Sunday June 16 2019, @04:11AM (4 children)
Well, you might be able to, and in fact there are cancer treatments which use heat to kill tumors. One is called HIFU https://stanfordhealthcare.org/stanford-health-care-now/2017/hifu-q-a.html [stanfordhealthcare.org] and it's being experimentally used to treat other tumors. In Canada they're trying external beam focused ultrasonic heating. I'm not sure how well it's working- I've heard mixed results, but again, it's fairly new.
In general, with radiation you might be able to very successfully kill, or surgically remove, a tumor, but they can spread, especially with surgery. The point here is that the cancer cells circulating in the blood spread the cancer (metastasize) to other organs, so they're trying to stop that. The traditional way has been to use chemotherapy to try to kill the spreading cells, but as most of us know, that can be pretty rough on the patient, and doesn't always work.
(Score: 0) by Anonymous Coward on Sunday June 16 2019, @04:33AM (1 child)
Are there little sharks with little lasers involved?
(Score: 1) by RandomFactor on Sunday June 16 2019, @03:39PM
I heard it was goldfish.
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(Score: 1) by RandomFactor on Sunday June 16 2019, @03:38PM (1 child)
A family member did the HIFU for Prostate cancer thing a couple of years back. Seems to have worked out.
HIFU is ultrasound based so a different heating mechanism that occurs at a focus point. Whatever is at that focus point is eliminated, so there is still going to be some collateral tissue damage. Even so, HIFU can be a big step forward as far as frequency and severity of side effects for treating that particular type of cancer.
That's what makes this intriguing to me, since this appears to interact specifically with the melanoma cells it might be very effective for this cancer as a tumor treatment option with no (or almost no) damage to nearby healthy tissue. I know that isn't what they were researching, but it does seem like an obvious avenue to pursue given their results.
The more miracle cures the better I sez :-P
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(Score: 3, Informative) by RS3 on Sunday June 16 2019, @06:23PM
Yes, HIFU is mostly being used for prostate cancer treatment, but mostly because of the physical technique. They build a tiny ceramic transducer, about the size of a kernel of rice, which is fed through the urethra into the center of the prostate, and energized. These are not focused- the energy radiates out pretty much in all directions. I think the number was 107F, which would cause brain damage, but most other organs would be okay. I have a friend who does cutting-edge ceramic transducer work and he occasionally tells me about projects like this where he was part of the R&D on this 10+ years ago. It's not limited to prostate, but that's the most common usage, mainly because it's the most minimally invasive use.
Yes, more cures, or at least treatments. Of course all cancers are different, and people's body chemistry, etc., so it can be difficult to know which treatment will work best for which problem. Things are getting better. :)