Slashdot Mirror
Treating Cancer with Beams of Anti-Matter
Zeinfeld writes "According to this Economist article scientists at CERN are using beams of antimatter to destroy cancer cells. The basic idea is that you make some anti-protons, whizz them round in a accelerator to get them moving at a decent rate then fire them at living tissue. They burrow down to the desired depth, find a friendly proton and do a spot of mutual anihilation, releasing sufficient energy in the process to kill a cell or two. The trick is that matter/anti-matter anihilation is a bit like nuclear fission, it does not work if the particles are moving too fast. The anti-proton has to be moving slowly enough to get pulled into the orbit of some atomic nucleus and actually collide. This allows the treatment to be fine tuned so it only affects the tissues at a very specific depth - unlike traditional therapies which zap everything in the line of fire."
So, sometime in the 1970s, MIT and Mass General were working on an experimental treatment called Boron Neutron Capture Therapy (BNCT for short). The idea was that you could fire thermal neutrons at a person, and they would only interact with elements that had a high neutron capture cross section, such as Boron or Gadolinium.
Neutron meets Boron, excitement ensues, cells die.
So, if you can add boron to a compound that is taken up preferentially by cancer cells, and then aim a thin beam of neutrons at the area of the tumor, then you will (theoretically) not kill anything but those cells.
The treatment was used mainly on large, likely-to-be-fatal brain tumors (at the time, they weren't candidates for operations). Unfortunately, most of the patients died anyway, sometimes from necrotic tissue or brain voids resulting from the decayed/destroyed tumor, sometimes because the boron containing compounds were not specific enough to cancer cells.
So the US stopped research on BNCT, but Japan and some other countries have continued the research, and I think recently some US researchers are thinking of taking it back up.
And the neutron source the MIT researchers used was their nuclear reactor (recently featured on NPR's "Wait, wait don't tell me"). One could presumably also use an accelerator.
-Marcus
It's incredibly simple. They divide. They don't do a perfect job when copying themselves. Occasionally they fuck up the bits that control their internal processes, like how fast they divide. All the wonderful chemicals we've surrounded ourselves with make 'em screw up more.
Unfortunately, it's not incredibly simple. Under normal circumstances, a cell has many checkpoints and regulatory processes to ensure that it doesn't divide too often and begin growing out of control. Cancerous cells have mutations or deficiencies at these control points. If you lose one or two of the control points, the cell can usually compensate. If you lose too many, the cell will divide out of control because growth will no longer be regulated - at this point, it's cancerous.
The checkpoints are lost through a few factors: chemicals and other carcinogens, genetic problems, and sometimes the cell just doesn't copy the DNA correctly. There's not just one cause for cancer in a cell. Usually, it's a combination of several factors.
The main problem with cancer is that it's so good at avoiding the body's immune system until the cancerous growth is fairly large. The cancer cells will stay away from the blood stream for a while, which lets it get big enough to cause a problem before it spreads to other parts of the body. That's why medicine has been pushing preventive screening - it's a lot easier to treat isolated cancer (which is harder to detect) than systemic cancer.