RPG's can be really broad.
The basic RPG has a simple leveling system, some stats, ect.
... but you have games like Borderlands, which take some RPG elements and put them, in this case, into a first person shooter.
1. You can have some different classes, instead of the usual warrior, mage and rouge, which we all know an love.
2. You can make the story lines differ from your actions, but also your stats and moral choices.
3. Maybe the dungeon is no ordinary dungeon, but a living being. Then you would have to ask some questions:
- Why is my character here?
- What is the dungeon?
- What does it want?
- ect.
Those are some of the many things that you can think of to kinda break away from the classic dungeon crawler-style RPGs.
I'm not saying that you have to break every fundamental thing about the genre.
Random-generating dungeon games are really popular right now too.
Hope I helped a bit and good luck