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Hospitals Look to a Nuclear Tool to Fight Cancer
The feed points us to a NYTimes article about hospitals using particle accelerators to treat cancer. While expensive, proponents say that the proton beams generated by the accelerators are more precise than conventional X-ray radiation therapy. This results in fewer side effects and reduced irradiation of surrounding tissue. The technology's critics say that the cost is not justified by a measurable increase in the level of care given to the patients. Nevertheless, this is an excellent example of "pure scientific research" leading to a useful, unrelated technique. From the NYTimes:
"Tumors in or near the eye, for instance, can be eradicated by protons without destroying vision or irradiating the brain. Protons are also valuable for treating tumors in brains, necks and spines, and tumors in children, who are especially sensitive to the side effects of radiation."
critics is just a shorthand for "Insurance Companies" right?
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possibly, but I'd rather be bombarded with focused protons than barely focused gamma/x rays.
protons have very little penetration power due to their high weight and volume. Normal alpha particle emitters, for example, are blocked simply by the lining of dead skin covering your body. Goggles and standard clothing will protect you from anything short of eating the particles.
Since they are accelerated, I'm guessing they penetrate further, but they will be stopped quicker too (charge, mass, volume, all these will make them easier to stop than high energy photon radiation). Best of all, it's the stopping/slowing of the protons that kills the cells (they hit stuff, break stuff, and stop/slow down), so less energy will be needed since the majority of the high-energy photons would just pass through. The trickiest part would be to determine how many protons and with how much energy.
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As another unrelated side benefit, you can strap it to your back and use it to catch ghosts.
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Focused protons would likely give you better superpowers, too. I mean, we all know what gamma rays do, and I, for one, don't want to prance around with green skin and purple short shorts when I'm angry.
Vincent J. Murphy
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Correct me if I am wrong (I am not in the US and haven't had any serious illnesses), but isn't medical insurance cover up to a certain limit of dollar value (usually extremely high), which makes the cost of a treatment irrelevant so long as it is scientifically proven to have a noticeable beneficial effect?
If insurance companies refusing a treatment over cost disgusts and shocks you, you might be interested to know that active government policy in every country with free health care (including those highlighted by Michael Moore in 'Sicko') consider on an ongoing basis as a matter of government policy which treatments that WILL NOT be given to people even if they are proven to cure, on the basis of costs, and the list is typically long. And as this case from the UK demonstrates;
http://news.bbc.co.uk/1/hi/england/cornwall/7151328.stm
Does it happen that you have a terminal illness that could be cured by a proven workable drug that is unfortunately not on the government-approved-expenses list? Too bad for you. Do you want to pay for this drug yourself? Well, that sucks, because you are not legally allowed to, in that case you would have to pay for your entire treatment yourself. Of course, you could always travel to a third-world country and have the drug illegally injected, at the risk of losing your house if it's discovered.
It would therefore shock my predictive abilities to the core if any country with a free and universal health care system offered particle accelerator treatments earlier than any country with privately funded health care.
This intended to balance out the general hatred for private medical companies and love for government health care systems with some hard facts and priorities that inevitably are going to be made.
For more information on proton beam therapy, albeit from a provider's point of view, here is a link to Loma Linda's Proton therapy page. (They were the first to set up a proton therapy center.) In addition to static informational and historical pages, there are also some videos explaining what they have to offer and how it works.
By contrast, accelerated protons deposit their energy almost evenly, at a relatively low rate, until they are slowed to a certain energy, at which point their deceleration rapidly increases, accompanied by a massive increase in linear energy deposition. This leads to the "Bragg Peak", which offers a much, much more accurately targeted beam than is possible with conventional sources. (See this illustration as an example - compare the red line (in this case, C12 ions, but a similar principle) to the green line (an 18MeV photon beam). By carefully tuning the beam energy and orientation this point can be scanned over the tumour volume, giving a very localised dose deposition.
What puzzles me is why this is news - I was under the impression that this concept is well-established, and has been fairly well verified already. Just some fluff to fill up the science and medicine section, maybe? Now if it was about the CERN anti-proton tests, that's certainly something with a more dubious cost/benefit analysis...
* - I say a few assumptions, these are basically the principle ones behind all radiotherapy - that is, that all dose at the end of track structures is created equal and all dose is bad according to the LNT. While these ideas may not be strictly true, it is unlikely for them to be so wrong that it would invalidate the treatment as a whole.
although 'modern' medicine offers some benefit, a lot of it is still 'guess your best' & experiment on the rest.
Some benefit? May I remind you that "Life expectancy at birth in the United States in 1900 was 47 years" (http://en.wikipedia.org/wiki/Life_expectancy)?
Compare that to the 77 years we enjoy today... But yeah, the fact that we live on average 30 years longer is just a detail.
For a nice picture of energy deposition vs. depth see e.g. http://www.gsi.de/forschung/bio/energy_e.html
One can adjust the peak energy deposition's depth by varying the proton's energy. The surrounding tissue gets a much lower dose than in X-Ray irradiations.
Combine the particle accelerator with a PET (http://en.wikipedia.org/wiki/Positron_emission_tomography) and you can irradiate a cancer with cubic millimeter resolution.
This is actually not a new, purely academic technique, it is already commercially available, see http://en.wikipedia.org/wiki/Proton_therapy
Attention: I'm not a doctor but a physics student :)
I visited a proton accelarator for cancer treatment near Ghent in Belgium 15 years ago. In which way is this new?
10 ?"Hello World" life was simple then
One thing: http://www.gsi.de/forschung/bio/energy_e.html is actually about heavy ions (carbon). The curve is not _too_ different for a proton, though.
Personally, who cares how expensive it is. I mean, we're not rich people and we are pretty close to that sarcastic "upper lower middle class" line.. but watching my wife go through chemo and surgery (no radiation, thank God) hurt me more than I can ever explain. If there was a way to make sure that radiation was a little "cleaner" and crisp around the edges, I'd say go for it. Chemo and surgery are hell enough.
Plus, x-rays are so last century. Everyone knows the new thing is protons.
Insurance companies frequently follow Medicare's lead, so we may find in a few years that we're paying gobs of money for proton beam treatments that do not offer better outcomes than alternatives. Once it gains acceptance as a standard treatment for cancers on which it offers no better outcome, we'll be paying a huge collective sum in taxes and insurance rates with no discernable benefit.
Oh my gosh! The FDA probably didn't realize that you disagree with the findings of the medical research! I'll let them know right away! We must get this information into the hands of oncologists immediately!
The article is mostly about the cost/benefit. The treatment has been around since 1990. Each center costs over $100M to build, so probably $10M/year to run. It can only treat a few thousand patients per year. At 2000/year and amortizing over 10 years, that's at least $10,000/patient just in facility cost. They say Medicare pays $50,000 per treatment so I can see why there is a rush to build these.
Intron: the portion of DNA which expresses nothing useful.
There's nothing new about using a "nuclear tool" in medicine.
http://outcampaign.org/
TFA is all about:
The relatively recent decision of some hospitals (and some entities that are set up to minimize economic risk rather than just do healthcare) to build a surprisingly large number of these very expensive, rather limited machines and
The lack of good science to suggest that, for most cancers, this technology is not any better than the older (still advanced, still expensive) gamma and x-ray treatments.
To my mind, the biggest WTF in the entire article is Medicare's decision to pay more for the proton beam therapy than the older ones, before solid information is available to say that it does or does not work any better than other therapies . You create a huge financial opportunity for investors without much in the way of benefit for society at large. The highway of modern medicine is littered with the personal and financial wrecks of treatments, medicines and ideas that seemed like a great idea at the time (else why do them) but turned out to work either less well than before or simply were much more expensive without significant clinical benefit.
Faster! Faster! Faster would be better!
Now, for me, personally, every single procedure that has a reasonable chance of giving me a normal lifespan (I'm under 30, so figure another 40-60 years) is worth it. I want to live - who doesn't? But reality is that I have an incredibly rare (synovial sarcoma, 800-1000 new cases per year in the US), which is functionally much different than carcinomas (all the big killers, lung/breast/colon, are carcinomas) there isn't much research being done and drugs that are developed for carcinomas don't work for sarcomas. The best drugs they have are decades old. Once my cancer recurred, statistics said I had a 5-8% chance of surviving 10 years.
Now, let's estimate that treating me over the last three years has cost half a million dollars. Was it worth it? For me, my family, my friends, yes, anything the doctors can do is worth it. (I should note that I have insurance, good insurance, because I happen to live in a state with a high-risk pool http://www.mchamn.com/) But was I overtreated, given the probability of a cure? Probably. But it's a lot easier for me to say that now that I don't have any good options left. This article is essentially about the fact that in order to control health care costs, we need to make the decision about how much money to spend on people like me before we treat them. I just read a NYT review of Overtreated http://www.nytimes.com/2007/12/19/business/19leonhardt.html?, which speaks to this very issue. There was one line I particularly liked:
because most Americans think it's the other guy who's getting unnecessary treatment How do you choose who to treat, and who not to treat, and when to stop treatment even though there are more procedures the doctors could do? Yes, proton therapy is better than LinAc-based radiation, but how much, and for whom, and are we willing to pay a lot more for a marginally better outcome? Each of us as individuals will always be willing to pay more, because the added cost is spread over the whole insurance pool. Of course this cost- and risk-spreading is the entire point and benefit of insurance, so we can't throw the baby out with the bathwater. But we need to find a way to decide what is good enough, and how much treatment is enough.
It isn't so much a question of how much we can afford, but how much we are willing to spend, how many other things we are willing to give up as health care spending displaces other spending. Given the urgency of the debate in the US over the rising cost of health care, we are close to or even already past what we prefer to spend on health care. Slowing and stopping the growth in cost ultimately means slowing and stopping the growth (relative to GDP, at least) the growth in care. The politicians won't say it, but that's reality.
How are you going to solve it? Not the NHS way; not the Medicare/Medicaid way. But somehow. And no matter what you choose, someone isn't going to get all the treatment they possibly could, and they might (probably will) be upset. You can see the result of NOT choosing. Time to decide.
This whole suggestion that Medical treatment with particle accelerators is new is not true. The use of such machines is stock medical stuff and has been so for more than 20 years. As to side effects, here is what my mother was told just after she drank some I-131 made in the local accelerator... In response to her question about cancer risk, she was told, "We don't think you will live that long."
The use of focused beams to shoot tumors is also 20 years old or more. The use of the beams to make Gama, X and even Neutron or Positron beams is not new as well. Sorry no news here folks! The Slashdot people got hornswoggled!
Never Politically Correct ~ I prefer the facts If you don't like what I say, get a life, or comment yourself.
For breast cancer the story is even better. The longterm survival rates for most breast tumors is identical between a masectomy and radiation. Bonus with radiation is: you give some dose to the surrounding tissues potentially killing secondary malignancies, and of course the woman still has a breast. The best treatment as far as survival goes is a lumectomy but this usually can only be done early stage (hence all the focus on breast screening).
Proton therapy has some potential, however, the main articles claim that protons are accurant where as X-rays are inaccurant is miss leading/wrong. Protons don't penetrate as far into tissue. Thus the radiation is more targetted for superficial treatments. However, the opposite is the case for treatment at depth. Since the protons deposit their energy relatively close to the surface, you'd need a much higher total dose to treat an internal organ then with X-rays. It really would depend on the malignancy and how much you want to spread the radiation over. Different types of radiation (and different energy levels, ie. 6MeV X-rays, 15 MeV X-rays), have different dose build up and fall off profiles. It really depends on where the tumor is which one will be the best.
In typical clinical process there is the point of interest (POI) and the target volume. These differ and sometimes by a wide margin. The target (ie where the radiation actually goes) is larger than the actual area that the oncologist thinks localizes the tumor. This is to allow for alignment errors (patient moves, machine tolerances etc), plus a safety margin (typically around 7mm) to try to get the stray cancer cells around the tumor. Anyways, the physician will prescribe a certain dose at a point in the target, and a percentage at a isosurface, so say 1000 Cy, 80% at POI + 7mm. At any rate you may not use the accuracy because you want some dose "off target" for localized tumor control (as apposed to general tumor control that you attempt with chemo).
X-ray treatment machines are much more accurate than claimed. Modern treatment units have among other things MLC (multi leaf collimaters) to shape the beam. You can thing of the beam like a light bulb, they place a bunch of retangular peices of metal between the patient and the bulb to get the desired shape. These are dynamically tuned so at one angle you might get 20% of the dose at a particular shape, and the rest at a different shape say, or they can be in motion during the "beam on" painting a more uniform distribution. At anyrate, a variety of angles (now in the works to use continuous arcs as well), and leaf positions enable you to paint the target with the 3 dimensional dose distribution you want with about 3mm spatial accuracy (add ins/some systems out of the box have about 5mm accuracy even after accounting for breathing in realtime on say a lung tumor), while spreading out the dose along the healthy tissue which reduces risk to the other areas. Also, newer machines can get an add on for about 600k that will enable the unit to act as a CT scanner (typical price 2-4M),