Hi JoJo,

All questions are welcome. Here's what I think:

Concurrent chemoradiation treatment (CRT) is a targeted treatment; it will only kill cancer cells in the region that's targeted. By doing the Induction Chemo (IC) first, they "mop up" most (hopefully all) of the cancer cells that have already escaped to other parts of the body. Yes, the IC might not kill them all, because some might be "robust", and any not killed by IC may end up causing your death. There are no guarantees here. In my view, if you don't do IC and only do CRT, then you haven't even tried to kill those few cancer cells that have escaped to other parts of the body. I think its worth trying.

But the above is merely a bunch of theorizing. I think it is important for researchers to develop (and then test, with the hope of verifying) theories as to what the mechanisms are, because doing so aids our understanding which can lead to ideas for even better treatments. But, from a purely clinical perspective, nobody cares much how it works. All that really matters is performance. Does the process lead to good outcomes? Its quite common that somebody has a clever idea for a new treatment that they think *should* work well, only to discover that it doesn't work at all - or that it works but has some unanticipated (and unacceptably bad) side effect. Would you want a treatment that cures your cancer but gives you excruciating pain for the rest of your life?

So clinicians rely on trials. Preferably large-scale placebo-controlled double-blind trials. For example, give 200 patients CRT but 100 of them get IC and 100 of them don't get IC. Then watch them awhile and see how long they live. If the patients that got IC live significantly longer than those who didn't get IC, and they don't suffer any unacceptable side effects, then it makes sense to give IC to future patients. To the clinician, it doesn't matter how or why IC gets the better result; it only matters *that* IC gets the better result.

On that basis, I'll refer you to two articles in the 25 Oct 2007 issue of the New England Journal of Medicine:

http://content.nejm.org/cgi/content/abstract/357/17/1695
http://content.nejm.org/cgi/content/short/357/17/1705

I also found this one fun to read:

http://jco.ascopubs.org/cgi/content/full/27/23/e52

But this might be easier to read:

http://www.ncbi.nlm.nih.gov/pubmed/18544437?dopt=Abstract

For the kinds of question you are asking, you need to look to this sort of technical literature to find your answers. The folks on this board are patients and patients usually don't know much about how or why different treatments work (or are chosen by their physicians). Patients can tell you their own experiences. But for the kinds of questions you are asking, all you'll get here is a bunch of well-meaning speculation (including my own). Train yourself to read and understand the technical articles... then go read them... and you'll know as much as anyone.

Hope that helps, Rob