Very valid points. I'm not saying this kind of work shouldn't be pursued, I just wanted to point out that it is premature to think of this device as a "breakthrough". As I said before, I hope it works, and new approaches are in general a good thing. I just think the way they are reported is more for entertainment purposes then spreading true knowledge.

Technically, the idea of killing a tumor w/ a localized toxin is in fact already widely used, not mechanically with tubes but with things like focused X-rays or molecular targeting (drugs that preferentially bind to cancer cells). While this helps, it rarely cures cancer because 1) by the time it is applied cancer cells have circulated throughout the body and seeded new tumors and 2) it's very difficult to kill 100% of cancer cells, and what winds up happening is you kill 99% of them that are most susceptible to being killed by chemo giving the 1% that is most resistant more room to grow. Hence the recurrence is much more difficult to treat.