We are all different and even though we all have cancer it affects each of us differently. Your husband can live a LONG time! I was diagnosed June 4, 2008 with stage IV adenocarcinoma (NSCLC), and both my lungs are compromised, but it has been over a year now and I'm still feeling fine. After chemo I went on Tarceva and there were times when the side effects were pretty awful, but they pass as your body adjusts to the meds. The Tarceva keeps the tumor in check, so, even though it doesn't go away, it isn't growing either.
I have never asked "how long". I know that I will have this for as long as I live, so I live the best I can everyday. Don't despair, and take every opportunity you can for joy -- the opportunities are endless!