[kiffl]

Let me just say first this is a very tough spot and I might be totally off. I read the big stack for a flush draw with a hand like KQ of spades, or QJ of spades. That would make sense for the way he has played the hand this far. I can't read him for AKs because I think he would raise under the gun with it. AA-QQ doesn't seem possible unless he is patient enough to set a trap and just smooth call the raise preflop. In this spot I think you should go all in because you can push out KQs or AKs which you don't want to allow to draw against you. The only problem is you could be almost dead vrs. AA or KK that is trapping. If you got the balls to risk your whole tournament in this spot go all-in, if not just check behind and play the river.