6 ms·

Researchers use lasers to detect and destroy tumor cells in melanoma patients

203 points by headalgorithm 7y ago

tombert 7y ago
These things never fail to get the same reaction from me: I get immediately excited, thinking that we've cured cancer, and then a bit depressed because this thing is probably a really long way away. I don't work in the medical industry, but to those that do, do these headlines irritate you?
- roywiggins 7y ago
  The good news is it's been in development for a decade already and the next step seems to be human trials for effectiveness, so it's still years away, but if it works out, maybe not that many.
- SubiculumCode 7y ago
  Cancer has turned out to be much harder than anyone realized 50 years ago...but the exciting thing over the last decade has been the major advances that have occurred, capitalizing on the basic biological research investments we've made. If anything, this is a story of how much we need to fund (and increase!) basic science research, even if it seems pointless in the near term.
- throwaway5752 7y ago
  Usually the big advances are built on a number of small incremental advances. Think about modern immunotherapy like CAR-T. Rather than recap myself I'm just going to post this timeline of the milestones that led to CAR-T over many decades: https://www.mskcc.org/timeline/car-t-timeline-progress https://www.mskcc.org/timeline/car-t-timeline-progress. You'll generally be disappointed, though. "Cancer" isn't really a thing. It is a family of disorders characterized by several properties that arises from different causes. At this point in my life, I am very confident that we will never have a single general cure for cancer (killing mutated cells, repairing carcinogenic dna damage).
- gus_massa 7y ago
  One very clear explanation of the problem is in a "PhD Comic" post: http://phdcomics.com/comics/archive.php?comicid=1162 http://phdcomics.com/comics/archive.php?comicid=1162 --- Also, remember that the fight against cancer is a marathon, not a sprint. It is like curing "virus infections" or curing "bacterial infections". It's imposible to cure them all with a magic weapon. Someone makes a new antibiotic/antiviral drug, someone makes a new vaccine, someone makes a new mixture to prevent dehydration, someone makes a new procedure to detect the infections. Each is only a step. Get happy for every step, but remember that it is only a step and there are a lot ahead. (Just ignore the press titles, assume they are always linkbait.)
- asdff 7y ago
  >do these headlines irritate you? Sometimes, but I'm usually not exposed to these news articles unless they are posted to hn or something. I prefer to go to the journal article over these written by journalists who don't have time to dig in and do a proper summary of the findings. Usually it goes something like this: 1. Interesting thing published in decent journal, but years away from clinical trials or even animal models and things fail during those tests all the time. 2. Journalist pumps out a half assed article about how its the new silver bullet. 3. Public reads the article, picks up that its remarkably similar to the half assed article they read on tuesday about a completely different thing in a completely different disease. 4. Public complains that there's "a new cure for cancer every day." 5. Public looses confidence in scientific authority. 6. Rinse and repeat when journals push the next batch of manuscripts next week. What's remarkable is that some of the biggest advances don't get very much coverage at all, or are covered for like a week or two and forgotten, despite the field mulling over and improving that finding for years. Clickbait-style news and scientific findings aren't compatible.
torpfactory 7y ago
Just gonna leave this here: https://xkcd.com/1217/ https://xkcd.com/1217/
- learc83 7y ago
  This was an in vivo experiment.
cwkoss 7y ago
It seems surprising that the laser has such selective activity on CTCs versus healthy cells. Why are these cells so much more absorbtive? Is this specific to melanoma CTCs (more pigment)? I also wonder how they did this measurement. Seems like you'd need to take pre- and post-laser measurements of healthy and CTC counts in the bloodstream to have high confidence that it is disproportionately damaging CTCs. To what extent does this damage healthy cells?
- nvusuvu 7y ago
  Even if it damaged/killed a small percentage of healthy cells, as long as it kills a much higher percentage of CTCs, hook me up. Good cells are replenished. So are the bad ones. Its an arms race!
- nvusuvu 7y ago
  Head researcher in 2003 pioneered the use of laser-induced vapor nanobubbles around overheated plasmonic nanoparticle clusters to kill single tumor cells without harming neighboring normal cells. https://news.uams.edu/2017/06/08/uams-researchers-kill-cancer-cells-using-nanobubble-spaser-as-the-worlds-smallest-laser/ https://news.uams.edu/2017/06/08/uams-researchers-kill-cance...
  - codesnik 7y ago
    Wow. That sounded like something from a comic book.
    - JulianMorrison 7y ago
      Make it so, Geordi.
ThomPete 7y ago
I've had two melanomas luckily early stage, I will likely get more so I am being checked 4-6 times a year plus doing molesafe. I'm at Sloan Memorial because I have more than a thousand moles. One thing we are using laser for is called Confocal wich basically allow them to see my cells live without having to do a biopsy. One of the two melanomas was found that way. I am always hopeful about new advances but I have learned that this is a long game and hopefully I am around long enough to reap the benefits if it goes seriusly wrong.
- JungleGymSam 7y ago
  Yes, this is exciting news. I've had melanoma once and one incident of basal cell. I get checked regularly and had three of four biopsies in the third and fourth stages of progression towards melanoma. Wonder why none of the doctors I've visited have mentioned Molesafe? I'll check it out when I get home. edit: Because Molesafe is NY/NJ only.
  - Shihan 7y ago
    Dysplastic Naevus Syndrome? There is a bunch of doctors/researchers who are telling that there isn't such a thing as dysplatic naevus. Well, of course you have that special looking mole, but the term "dysplatic" is misleading and also the concept that there is a development of moles from benign to cancerous. A mole was either always a melanoma (or a melanoma inside a mole) or it was and is a normal mole (and will be one).
    - ThomPete 7y ago
      My dermatologist is Dr. Marghoo, he writes a lot of the books on melanomas and is one of the biggest experts in the world in this matter. I think he would say it exist but I can ask him next time. https://www.mskcc.org/cancer-care/doctors/ashfaq-marghoob https://www.mskcc.org/cancer-care/doctors/ashfaq-marghoob
    - JungleGymSam 7y ago
      I hope I can remember to ask my Dr. about this next time I go in.
maxander 7y ago
An old XKCD is, as usual, highly relevant: https://xkcd.com/1217/ https://xkcd.com/1217/ Granted, this is actually a trial in humans, so that's good! But if you look at the study, the focus is on detecting circulating cancer cells; attempting to use the technology to destroy them is relegated to one paragraph near the end. There they note that this seemed to happen by accident, to a limited degree, in 6 out of the 18 patients; so they tried again in a single patient, whose melanoma cell melanin content was particularly favorable for this process, and it again seemed to work ("up to a 48-fold reduction" in circulating melanoma cells.) They went on to do in vitro tests to try and show it would work in general, aiming the laser at a test tube full of blood; this worked, which is encouraging, but it shouldn't be taken as a strong indicator of anything practical. (And even there, they note that the melanin content of the tumor cells is important to the treatment's effectiveness.) And yes, it's only targeting circulating melanoma cells. This tech can't just aim a laser at a tumor and kill it; it probably isn't useful for non-solid cancers like leukemia, either. So while this is cool and interesting, it's not a huge breakthrough in cancer treatment.
- arkades 7y ago
  The XKCD is spot-on here. > “In one patient, we destroyed 96 percent of the tumor cells” that crossed the laser beam, says Zharov. Just want to clarify: tumors will generally drop hundreds of thousands to millions of cells into the blood stream on a daily basis. Most of the circulating tumor cells are already unlikely to become mets at baseline, and by the time you've found a tumor you've already seeded these cells in a number of locations throughout the body. This seeding usually occurs long before we can detect the primary tumor. We get "metastasis" when a number of other factors come into play that allow a particular CTC / bundle of CTCs to start growing into a met. For those interested, R. Weinberg's text on cancer is pretty much the authority, and he discusses this at length. As it exists, as a therapy, it's for catching some of the horses that are making it out of the barn - after the doors have been open for a while. To be useful as a therapy, we'd need something that can be worn 24/7 - if I catch a tumor that needs to be excised, I'd put it on your arm, and use it to deplete the circulating population to reduce the likelihood of metastasis happening in the period between detection and excision. And I'd need an RCT to show me that this is actually going to result in a reduction of metastasis, since there's every likelihood that the eventual met won't come from the CTCs seeded in the period between detection and excision. Don't get me wrong; I'm happy to see more ways to detect and kill tumor cells. But this is still many steps away from becoming a technology with clinical application. At this stage, its relationship to useful cancer therapy is the relationship between my laser pointer from ten years ago and a sci-fi laser pistol. What this is cool as, is as a mechanism for helping detect cancers. I'm all for having something I can slap on your arm and let me know if you've got melanoma brewing, rather than having a dermatologist manually inspect all your crevices for an overlooked mole.
apo 7y ago
The problem with fighting cancer is selectively destroying cancer cells while leaving normal cells alone. This article unfortunately says nothing about how this device does so (or even whether it does). Without some handle on this aspect, side effects (some of which might show up much later) could be a major problem with this treatment. No time to plow through the original paper - does anyone know?
- doctoboggan 7y ago
  Yes, the linked article addresses exactly that: The laser, beamed at a vein, sends energy to the bloodstream, creating heat. Melanoma CTCs absorb more of this energy than normal cells, causing them to heat up quickly and expand. This thermal expansion produces sound waves, known as the photoacoustic effect, and can be recorded by a small ultrasound transducer placed over the skin near the laser. The recordings indicate when a CTC is passing in the bloodstream. The same laser can also be used to destroy the CTCs in real time. Heat from the laser causes vapor bubbles to form on the tumor cells. The bubbles expand and collapse, interacting with the cell and mechanically destroying it.
deleted 7y ago
[deleted]
killjoywashere 7y ago
The title should be updated to read "circulating tumor cells". Major biologic difference.
deleted 7y ago
[deleted]
drenvuk 7y ago
I'm not sure if this is silly or not but why is it not possible to target cancer cells with a bunch of weak lasers distributed around a person pointing at the same location in 3d space and just selectively zapping them? We have real time MRIs and CT scans. Can't we just lie people with cancer down daily and shoot them with incredibly precise beams of light to cook the cancer cells alive? Maybe just cauterizing the blood pathways that are feeding tumors in the first place? I'm seriously hoping someone can tell me why this idea is stupid.
- sxg 7y ago
  It's not stupid, and we already do this. There are many different forms of radiation therapy (https://en.wikipedia.org/wiki/Radiation_therapy https://en.wikipedia.org/wiki/Radiation_therapy), and they're commonly used in breast and brain cancers.
  - drenvuk 7y ago
    Thank you for the link. I was reading this section and it seems that accuracy https://en.wikipedia.org/wiki/Radiation_therapy#Medical_uses https://en.wikipedia.org/wiki/Radiation_therapy#Medical_uses and movement are the main things that hold it back. I hope they can remedy that.
    - sxg 7y ago
      There are some other limitations as well. Radiation therapy can cause scarring in different tissue types. The scarring can sometimes be problematic depending on the location and extent. Second, the radiation itself can lead to the development of secondary cancers. Often, younger patients with lymphoma receive radiation to the neck area, which can cause thyroid cancers later in life. Despite these drawbacks, radiation therapy is massively beneficial and great for patients. The whole therapy is delivered in ~30 minute sessions over the course of a few weeks, and the entire procedure is painless.
  - wizardforhire 7y ago
    Totally! Also for whomever else reading this thread, I’ve been privy to quite a few medical tech startups and let me please share, it’s much simpler than one might imagine to create new medical tech. It’s a remarkably underserved area, the requirements are not quite as hard to get through as it would seem from first glance and I’ve been appalled at many of the systems that are in current use at many hospitals. We’re talking Stone Age level in a lot of ways! If you’re humble, willing to go in and actually listen to the doctors and nurses to identify the real problems and willing to create robust solutions it’s practically the Wild West of opportunities.
LinuxBender 7y ago
When will this be generally available everywhere?
ricardobeat 7y ago
Could this be made a lot more efficient by combining with dialysis, i.e. targeting the cells in a dedicated blood-pumping machine with more surface area, no skin layer and less worries about collateral damage?
- reubens 7y ago
  The beauty of it is that no blood need be removed. That is a huge improvement in terms of patient experience.
Haga 7y ago
If you could embed a Fibre web in deep tissue and give the machine a scan technologie and a waytto move the endpoints, you could micro dose suspicious tissue.
nn3 7y ago
And? Won't the migrating cells just keep coming unless you target the original cancer too? It seems like a very temporary improvement at best. Missing part of the idea here.
- asdff 7y ago
  No one gets their cancer cured, just hopefully into remission. No matter the therapy there will always be a few cancer cell populations that evade treatment. This is why cancer patients are monitored for life.

203 points by headalgorithm 7y ago

These things never fail to get the same reaction from me: I get immediately excited, thinking that we've cured cancer, and then a bit depressed because this thing is probably a really long way away. I don't work in the medical industry, but to those that do, do these headlines irritate you?

roywiggins 7y ago
The good news is it's been in development for a decade already and the next step seems to be human trials for effectiveness, so it's still years away, but if it works out, maybe not that many.
SubiculumCode 7y ago
Cancer has turned out to be much harder than anyone realized 50 years ago...but the exciting thing over the last decade has been the major advances that have occurred, capitalizing on the basic biological research investments we've made. If anything, this is a story of how much we need to fund (and increase!) basic science research, even if it seems pointless in the near term.
throwaway5752 7y ago
Usually the big advances are built on a number of small incremental advances. Think about modern immunotherapy like CAR-T. Rather than recap myself I'm just going to post this timeline of the milestones that led to CAR-T over many decades: https://www.mskcc.org/timeline/car-t-timeline-progress https://www.mskcc.org/timeline/car-t-timeline-progress. You'll generally be disappointed, though. "Cancer" isn't really a thing. It is a family of disorders characterized by several properties that arises from different causes. At this point in my life, I am very confident that we will never have a single general cure for cancer (killing mutated cells, repairing carcinogenic dna damage).
gus_massa 7y ago
One very clear explanation of the problem is in a "PhD Comic" post: http://phdcomics.com/comics/archive.php?comicid=1162 http://phdcomics.com/comics/archive.php?comicid=1162 --- Also, remember that the fight against cancer is a marathon, not a sprint. It is like curing "virus infections" or curing "bacterial infections". It's imposible to cure them all with a magic weapon. Someone makes a new antibiotic/antiviral drug, someone makes a new vaccine, someone makes a new mixture to prevent dehydration, someone makes a new procedure to detect the infections. Each is only a step. Get happy for every step, but remember that it is only a step and there are a lot ahead. (Just ignore the press titles, assume they are always linkbait.)
asdff 7y ago
>do these headlines irritate you? Sometimes, but I'm usually not exposed to these news articles unless they are posted to hn or something. I prefer to go to the journal article over these written by journalists who don't have time to dig in and do a proper summary of the findings. Usually it goes something like this: 1. Interesting thing published in decent journal, but years away from clinical trials or even animal models and things fail during those tests all the time. 2. Journalist pumps out a half assed article about how its the new silver bullet. 3. Public reads the article, picks up that its remarkably similar to the half assed article they read on tuesday about a completely different thing in a completely different disease. 4. Public complains that there's "a new cure for cancer every day." 5. Public looses confidence in scientific authority. 6. Rinse and repeat when journals push the next batch of manuscripts next week. What's remarkable is that some of the biggest advances don't get very much coverage at all, or are covered for like a week or two and forgotten, despite the field mulling over and improving that finding for years. Clickbait-style news and scientific findings aren't compatible.

torpfactory 7y ago

Just gonna leave this here: https://xkcd.com/1217/ https://xkcd.com/1217/

learc83 7y ago
This was an in vivo experiment.

cwkoss 7y ago

It seems surprising that the laser has such selective activity on CTCs versus healthy cells. Why are these cells so much more absorbtive? Is this specific to melanoma CTCs (more pigment)? I also wonder how they did this measurement. Seems like you'd need to take pre- and post-laser measurements of healthy and CTC counts in the bloodstream to have high confidence that it is disproportionately damaging CTCs. To what extent does this damage healthy cells?

nvusuvu 7y ago
Even if it damaged/killed a small percentage of healthy cells, as long as it kills a much higher percentage of CTCs, hook me up. Good cells are replenished. So are the bad ones. Its an arms race!
nvusuvu 7y ago
Head researcher in 2003 pioneered the use of laser-induced vapor nanobubbles around overheated plasmonic nanoparticle clusters to kill single tumor cells without harming neighboring normal cells. https://news.uams.edu/2017/06/08/uams-researchers-kill-cancer-cells-using-nanobubble-spaser-as-the-worlds-smallest-laser/ https://news.uams.edu/2017/06/08/uams-researchers-kill-cance...
- codesnik 7y ago
  Wow. That sounded like something from a comic book.
  - JulianMorrison 7y ago
    Make it so, Geordi.

ThomPete 7y ago

I've had two melanomas luckily early stage, I will likely get more so I am being checked 4-6 times a year plus doing molesafe. I'm at Sloan Memorial because I have more than a thousand moles. One thing we are using laser for is called Confocal wich basically allow them to see my cells live without having to do a biopsy. One of the two melanomas was found that way. I am always hopeful about new advances but I have learned that this is a long game and hopefully I am around long enough to reap the benefits if it goes seriusly wrong.

JungleGymSam 7y ago
Yes, this is exciting news. I've had melanoma once and one incident of basal cell. I get checked regularly and had three of four biopsies in the third and fourth stages of progression towards melanoma. Wonder why none of the doctors I've visited have mentioned Molesafe? I'll check it out when I get home. edit: Because Molesafe is NY/NJ only.
- Shihan 7y ago
  Dysplastic Naevus Syndrome? There is a bunch of doctors/researchers who are telling that there isn't such a thing as dysplatic naevus. Well, of course you have that special looking mole, but the term "dysplatic" is misleading and also the concept that there is a development of moles from benign to cancerous. A mole was either always a melanoma (or a melanoma inside a mole) or it was and is a normal mole (and will be one).
  - ThomPete 7y ago
    My dermatologist is Dr. Marghoo, he writes a lot of the books on melanomas and is one of the biggest experts in the world in this matter. I think he would say it exist but I can ask him next time. https://www.mskcc.org/cancer-care/doctors/ashfaq-marghoob https://www.mskcc.org/cancer-care/doctors/ashfaq-marghoob
  - JungleGymSam 7y ago
    I hope I can remember to ask my Dr. about this next time I go in.

maxander 7y ago

An old XKCD is, as usual, highly relevant: https://xkcd.com/1217/ https://xkcd.com/1217/ Granted, this is actually a trial in humans, so that's good! But if you look at the study, the focus is on detecting circulating cancer cells; attempting to use the technology to destroy them is relegated to one paragraph near the end. There they note that this seemed to happen by accident, to a limited degree, in 6 out of the 18 patients; so they tried again in a single patient, whose melanoma cell melanin content was particularly favorable for this process, and it again seemed to work ("up to a 48-fold reduction" in circulating melanoma cells.) They went on to do in vitro tests to try and show it would work in general, aiming the laser at a test tube full of blood; this worked, which is encouraging, but it shouldn't be taken as a strong indicator of anything practical. (And even there, they note that the melanin content of the tumor cells is important to the treatment's effectiveness.) And yes, it's only targeting circulating melanoma cells. This tech can't just aim a laser at a tumor and kill it; it probably isn't useful for non-solid cancers like leukemia, either. So while this is cool and interesting, it's not a huge breakthrough in cancer treatment.

arkades 7y ago
The XKCD is spot-on here. > “In one patient, we destroyed 96 percent of the tumor cells” that crossed the laser beam, says Zharov. Just want to clarify: tumors will generally drop hundreds of thousands to millions of cells into the blood stream on a daily basis. Most of the circulating tumor cells are already unlikely to become mets at baseline, and by the time you've found a tumor you've already seeded these cells in a number of locations throughout the body. This seeding usually occurs long before we can detect the primary tumor. We get "metastasis" when a number of other factors come into play that allow a particular CTC / bundle of CTCs to start growing into a met. For those interested, R. Weinberg's text on cancer is pretty much the authority, and he discusses this at length. As it exists, as a therapy, it's for catching some of the horses that are making it out of the barn - after the doors have been open for a while. To be useful as a therapy, we'd need something that can be worn 24/7 - if I catch a tumor that needs to be excised, I'd put it on your arm, and use it to deplete the circulating population to reduce the likelihood of metastasis happening in the period between detection and excision. And I'd need an RCT to show me that this is actually going to result in a reduction of metastasis, since there's every likelihood that the eventual met won't come from the CTCs seeded in the period between detection and excision. Don't get me wrong; I'm happy to see more ways to detect and kill tumor cells. But this is still many steps away from becoming a technology with clinical application. At this stage, its relationship to useful cancer therapy is the relationship between my laser pointer from ten years ago and a sci-fi laser pistol. What this is cool as, is as a mechanism for helping detect cancers. I'm all for having something I can slap on your arm and let me know if you've got melanoma brewing, rather than having a dermatologist manually inspect all your crevices for an overlooked mole.

apo 7y ago

The problem with fighting cancer is selectively destroying cancer cells while leaving normal cells alone. This article unfortunately says nothing about how this device does so (or even whether it does). Without some handle on this aspect, side effects (some of which might show up much later) could be a major problem with this treatment. No time to plow through the original paper - does anyone know?

doctoboggan 7y ago
Yes, the linked article addresses exactly that: The laser, beamed at a vein, sends energy to the bloodstream, creating heat. Melanoma CTCs absorb more of this energy than normal cells, causing them to heat up quickly and expand. This thermal expansion produces sound waves, known as the photoacoustic effect, and can be recorded by a small ultrasound transducer placed over the skin near the laser. The recordings indicate when a CTC is passing in the bloodstream. The same laser can also be used to destroy the CTCs in real time. Heat from the laser causes vapor bubbles to form on the tumor cells. The bubbles expand and collapse, interacting with the cell and mechanically destroying it.

deleted 7y ago

[deleted]

killjoywashere 7y ago

The title should be updated to read "circulating tumor cells". Major biologic difference.

deleted 7y ago

[deleted]

drenvuk 7y ago

I'm not sure if this is silly or not but why is it not possible to target cancer cells with a bunch of weak lasers distributed around a person pointing at the same location in 3d space and just selectively zapping them? We have real time MRIs and CT scans. Can't we just lie people with cancer down daily and shoot them with incredibly precise beams of light to cook the cancer cells alive? Maybe just cauterizing the blood pathways that are feeding tumors in the first place? I'm seriously hoping someone can tell me why this idea is stupid.

sxg 7y ago
It's not stupid, and we already do this. There are many different forms of radiation therapy (https://en.wikipedia.org/wiki/Radiation_therapy https://en.wikipedia.org/wiki/Radiation_therapy), and they're commonly used in breast and brain cancers.
- drenvuk 7y ago
  Thank you for the link. I was reading this section and it seems that accuracy https://en.wikipedia.org/wiki/Radiation_therapy#Medical_uses https://en.wikipedia.org/wiki/Radiation_therapy#Medical_uses and movement are the main things that hold it back. I hope they can remedy that.
  - sxg 7y ago
    There are some other limitations as well. Radiation therapy can cause scarring in different tissue types. The scarring can sometimes be problematic depending on the location and extent. Second, the radiation itself can lead to the development of secondary cancers. Often, younger patients with lymphoma receive radiation to the neck area, which can cause thyroid cancers later in life. Despite these drawbacks, radiation therapy is massively beneficial and great for patients. The whole therapy is delivered in ~30 minute sessions over the course of a few weeks, and the entire procedure is painless.
- wizardforhire 7y ago
  Totally! Also for whomever else reading this thread, I’ve been privy to quite a few medical tech startups and let me please share, it’s much simpler than one might imagine to create new medical tech. It’s a remarkably underserved area, the requirements are not quite as hard to get through as it would seem from first glance and I’ve been appalled at many of the systems that are in current use at many hospitals. We’re talking Stone Age level in a lot of ways! If you’re humble, willing to go in and actually listen to the doctors and nurses to identify the real problems and willing to create robust solutions it’s practically the Wild West of opportunities.

LinuxBender 7y ago

When will this be generally available everywhere?

ricardobeat 7y ago

Could this be made a lot more efficient by combining with dialysis, i.e. targeting the cells in a dedicated blood-pumping machine with more surface area, no skin layer and less worries about collateral damage?

reubens 7y ago
The beauty of it is that no blood need be removed. That is a huge improvement in terms of patient experience.

Haga 7y ago

If you could embed a Fibre web in deep tissue and give the machine a scan technologie and a waytto move the endpoints, you could micro dose suspicious tissue.

nn3 7y ago

And? Won't the migrating cells just keep coming unless you target the original cancer too? It seems like a very temporary improvement at best. Missing part of the idea here.

asdff 7y ago
No one gets their cancer cured, just hopefully into remission. No matter the therapy there will always be a few cancer cell populations that evade treatment. This is why cancer patients are monitored for life.