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.
Now I can see your point. Thanks for the reply. However, this treatment is not only about localized toxin. It has a two-fold approach of both blocking the blood path the tumor is feeding of and using a localized chemo treatment. Wouldn't this approach be more effective than the actual ways?
I have another question. Since you claim that localized toxin causes the recurrence to be much more difficult to treat because the 1% that survives is resistant to chemo, wouldn't an unlocalized toxin be much worse because not only it would also not kill these 1% that was resistance, but also it would kill less of those 99% susceptible and would also kill some healthy cells, making the body weaker and the recurrence to occur sooner?
sure =). I'm an engineer and not an oncologist so don't quote me on this. The main msg is that treating cancer is really, really hard; as another commenter noted biology is incredibly complicated.
multi-pronged approaches do seem to work best; some variation of that already happens. Large tumors are surgically removed, anti-angiogenesis drugs work by blocking new blood vessels from growing, I mentioned some others. The problem is that even the most aggressive combinations of treatments haven't proved to actually work in practice, and death rates for most cancers have barely budged in the last 30 yrs. A reflection of this is that people will pay $50k+ for a drug that will increase life expectancy by a few weeks (or their insurance will, that's another topic).
People like me do train their entire lives to improve this, and we are working on many new possibilities, for example tracking circulating tumor cells and figuring out what DNA mutations they have to see if you can make a drug that is targeted towards deactivating whatever fraction of them actually lead to metastatic disease. Look up the National Cancer Institute's nanotechnology in cancer program to see more of this kind of stuff.
I don't know what the "unlocalized" side effects are and why things are done that way - I will say any kind of advance in treaments is incredibly difficult to achieve because you have to convince MDs and patients to go with something new when there is a tried and tested method, and it is their lives in the balance.
The problem is that even the most aggressive combinations of treatments haven't proved to actually work in practice, and death rates for most cancers have barely budged in the last 30 yrs.
I can't help you with a citation for that, but I can give you citations for the opposite claim "A major decline in cancer mortality has been occurring in the United States for the past 50 years, affecting birth cohorts born as long as 80 years ago. [...] These findings suggest that improvements in cancer detection, treatment, and/or prevention have reduced the risk of cancer death across the life span for individuals born in the last three quarters of the 20th century.":
The problem with moderation on HN (and other sites) is that all you have to do to be upmodded is to assert something firmly enough. It doesn't have to be even remotely true; people will mod it up regardless. Annoying as hell, and potentially destructive to public discourse when it's as blatantly wrong as the grandparent's post was.
I think comments are good for adding perspective. You shouldn't expect an expert to arrive and give a concise, absolutely true and exhaustive explanation with that perspective. Spurring a community to dig deeper on something previously assumed true is a good thing, right?
The article cited does not claim we've improved cancer treatments - only that mortality from cancer for certain age groups has decreased according to their analysis, which could be from a number of reasons. To my knowledge, one of those reasons is not that a variety of prevalent cancers has been cured to any substantial degree. Also, just because you can find a published article that claims something doesn't mean it's true (although it is a much better chance in the scientific literature versus popular press due to peer review). Especially in an active area like cancer with 10k+ papers, you can basically find a paper that will support any viewpoint.
The NYT is running a great series on cancer treatment that gets into these matters, I should have cited before, here's one of them:
>>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.
Isn't the point of a device like this that it can increase the concentration of chemo in tumors while keeping the concentration as low as possible in non-cancerous tissue?
Which should help that point (that is, manage to kill off enough cancer cells that the immune system or some other treatment can wipe out any surviving).
(As someone else noted, the article referenced some paper supporting doing this method.)
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.