Antimatter Cancer Therapy (long)

Factual Questions
1

At DragonCon this past weekend, as part of the Science programming track, a physicist named Steven D. Howe made a presentation on “Profitable Uses of Antimatter.”

He has formed a company called P Bar Technologies which is building a facility at Fermilab to harvest some of the antiprotons they create. These will be used to treat cancer. Here’s what he told us:

X-ray therapy only destroys cancer cells when they’re dividing, which no more than 7% of them are doing at any one time. So you have to repeat it many times for effective treatment. And there’s collateral damage to healthy tissue.

Proton emission therapy is better, because you can fire it at a velocity that allows it to pass harmlessly through the skin and intervening healthy tissue without damaging it, then hitting the tumor cells and knocking some out. But there isn’t much “bang” for the buck.

Firing large ions at the cancer provides substantial “bang,” but they damage tissue on the way in.

Okay, so what about antiprotons? This is great: fire an antiproton into a tumor, adjusting the speed so it comes to a stop right where you want it to. It damages no healthy tissue on the way in. It hits a large molecule, say a carbon or oxygen molecule, and annihilates all but the nucleus. Instant large ion, which then goes “bang” and destroys everything within three cell diameters.

They keep firing antiprotons until the tumor’s gone. They use, uh, some kind of tomography to make a 3d map of the patient’s body. Crablike brain tumor with many tendrils? No problem. The thing’s accurate to within a few millimeters, and reduces the number of live cancer cells to the point where the patien’t considered cured.

Dr. Howe claimed they’ll be up and running in 13-15 months and will be able to treat 500 patients a year for around $20,000.

I posted this OP mainly because this just seemed so cool, but I do also have a GQ, which is as follows:

So you’ve got a mass of dead tissue inside your body that used to be a tumor. What becomes of it? Could it cause problems? Dr. Howe admitted he had no idea.

Besides that, can anyone see any problems with this therapy aside from its scarcity (there are 500,000 new cancer patients every year)?

2

I have absolutely nothing useful to contribute, but I just wanted to pop in to say that I too was at DragonCon. Small world. I’m afraid I missed that particular talk (I think C3PO was also speaking at that time), but I did spend most of the weekend in the Space Track. Cool stuff, especially the talks given by Dani Eder. I’d ask which one you were, but unless you were the one with the Wookie costume, I probably wouldn’t remember.

Since I have a degree in biology, I guess I’ll throw out a WAG: I would guess that dead tumor cells would be absorbed by lymphocytes, broken down into component parts and molecules, and recycled. Just like other cells that die in the body.

-b

3

Juliet Prowse was the one in the Wookiee costume.

A fellow Doper who was also at the convention, who’s getting a doctorate in molecular biology, said the dead tumor cells wouldn’t be reabsorbed. I don’t recall why; maybe he’ll come to this thread.

4

If she’s a friend of yours, please commend her on her incredible costume. (There’s a pic we took of her here.)

Well, I can’t think of any reasons for this to be so off the top of my head, but then again, I’m not up for a doctorate, so I’ll assume he knows what he’s talking about.

-b

5

IANAMoleBio, just married to one. Sounds like a bunch o’ crap to me.

How do you adjust the speed to get it to stop where you want?

What is special about tumorous cells to stop the antiproton?

Aren’t antiprotons ridiculously expensive to produce? Is Fermilab giving them away for free? Even at $20,000 a pop, it doesn’t seem like enough to cover expenses.

I thought antiprotons would explode with the first proton they met, whether that be air, skin, or tumor.

What the heck is a physicist/businessman doing publicizing his idea at DragonCon? Has he written it up for any respectable scientific publication? Has it been peer-reviewed?

Is this NCI approved? You can’t legally treat people with a new therapy like this unless it’s been approved. Where’s the molecular studies, the animal studies, the Phase I and Phase II trials… instead he’s at DragonCon?

Can’t say I’m the most educated person to speak on this, but I’m not the least either. Sound ridiculous.

6

A particle with speed x will be able to travel a certain average distance through a material before hitting something. Remember that matter is mostly empty space. So if you know your particles have to go through 2.5cm of tissue, you give them just the right energy so that their average stopping point is at that depth. Of course, some will go more or less, and will do some damage, but most will be around that depth. I imagine you would use magnets to adjust the speed of the antiprotons (which have a negative charge) the same way your TV tube channels and directs electrons.

Nothing. It is just that at that speed (i.e. with that much energy) they can penetrate to that particular depth.

Yes, they will. Remembering, again, that air, tissue, whatever is mostly empty space, it will be a while (albeit a short while) before they encounter a proton. This will result in a very tiny “poof” for an individual pair of particles.

-b

7

Remember the source, folks. This was presented at Dragoncon, not at the National Cancer Institute. The theory may be interesting, but a number of technical problems remain.

8

They’re getting the antiprotons from FermiLab; they’re taking a tiny portion of FermiLab’s output, about 10[sup]12[/sup] antiprotons a year. The trap they’ll gather and keep them in has already been built.

So, that’s how they get the antiprotons. I don’t think FermiLab gives them away, but Dr. Howe is an insider; he worked for Los Alamos for 22 years. So I’m sure they cut his company a deal. At $20,000 per treatment he said they will become profitable within 2.5 years of operation.

They’re already building the facility and will begin trials on mice in about a year, with the first trials on (volunteer) humans to follow soon after. He didn’t say anything about NCI, but he did say they don’t need FDA approval; not sure why but it was something about how they don’t cross state lines with the device, and it’s not a drug.

Why was he telling us all this at DragonCon? Because they invited him to. I don’t see how that stains his credibility.

9

doesn’t the annihilation of matter in a proton/antiproton collision release a lot of energy? wouldn’t that be harmful to the patient?

10

Yes, Mangetout, it releases quite a lot of energy; it basically causes a tiny explosion which spans three cell diameters. That’s huge when you consider that you started with the mass of one ionic molecule, but not when you consider how many cells are in the body. There’s no release of gamma rays or other radiation like with an atomic bomb, though, if that’s what you’re wondering.

11

Oh, right, that sounds ideal then.

tell me, is it possible to use a magnetic field to slow the antiprotons down drastically at a certain point? - once they have entered the right bit of flesh (I’m just thinking that this might be a way of reducing the collateral damage from those few that overshoot the tumour or just happen to collide before they get there).

12

I guess I’ll shut up and see what happens.

If interested, here are a few references on the guy:
http://www.lunatechpress.com/howebio.html
hbar.fnal.gov/meetings/june_7_2000/agenda.htm

13

Well, Mangetout, all the containment and manipulation of the antimatter is done with magnets (obviously), but more specifically how I couldn’t say.

Incidentally, the title of Dr. Howe’s presentation was “Profitable Uses of Antimatter” and he began by saying he originally looked at antimatter as a possible power source for spacecraft (which has been the presumed future application of antimatter for decades now).

Antimatter would be a great power source for deep space missions, but you’d need far too much of it to be cost-effective. To power a craft to Alpha Centauri in a reasonable time frame you’d need several kilograms of the stuff.

And it currently costs $6 trillion per gram.

Oh, aside to bryanmcc: The Juliet Prowse thing was a joke. Juliet Prowse was a famous leggy dancer, and I was humorously juxtaposing her with David Prowse, who I thought played Chewbacca in the movies. Except he didn’t, so I’m just an idiot.

14

So does no one have any idea what happens to the dead tumor?

15

I don’t know how much credibility I have on this thread, but…

I would think the dead tumor would be treated as waste, and processed by the body as such.

16

it would seem that, if the antiprotons are causing tiny cell-sized explosions in there, that whatever is left is going to be just mashed dead tissue, like you would get with any other trauma, since this isn’t open to the air, it shouldn’t be too prone to infection and I would imagine the body would just gradually clear it away like it does with a bruise.

17

This sounds a lot like gamma knife therapy.

Gamma knife is where they carefully position a cancer patient in front of the business end of a particle accelerator (this is not only a position in space but a very careful imobilization) and shoot gamma radition through the tumor. They actually attack it from several intersecting angles, so that while healthy tissue does take some damage, it’s damage that can be repaired but the tumor, at intersections of the angles used for gamma zapping, accumulates enough damage to die.

It’s expensive and from what I’ve read is usually used on brain tumors that are otherwise inoperable, but is now being used on operable tumors that meet certain specifications. It’s usually done in a series of treatments so the body can clear away debris and heal sub-lethal damage, then another zap, more clean up, and so on. I gather that if you completely zapped a large tumor you run the risk of an abcess or other nasty complication forming.

Seems to me the use of anti-matter would be just another way to get radition into the body in a (hopefully) controlled manner.