Sadly no there isn't.

you can't you're fucked, but don't get sad, here take  Peter, he will cheer you up.

i hope they patch it. I cant believe this was overlooked

not being able to back out is like a staple of any old fighting game
 
also kitty!

You can't just patch out something that's been in the game for 8 years.

That's kind of how old Arcade fighting games used to be.  SSF2THDR basically has the same thing going for it.  Lame?  Yes.  Fixable in a sequel?  If that cold day in hell happens.

I hate when I'm picking characters too fast and I accidentally pick the wrong one and I can't back out. It's game over if I suck with the character.

Welcome to Fighting Games 101.

I don't get why fighting games have to do stuff like that. They also don't like actually putting the actual button in the controls, and instead put some weird arcade controls.

Blazblue lets you do get out of the screen if you push select. More fighting games nees to start doing that

That has been in MvC2 since its original release. all console releases have been ports of the arcade version, the DC being the best

Exiting anything is pretty rough in this game.  Often times I get trapped in spectator mode and the game won't let me exit the lobby after a fight ends.  If i've won and i'm tired, sometimes the game goes right from the end of the match stat screen to character select and you can't leave without exiting to the Dashboard.
 
There's alot of stupid little things like that.  I feel like, if its a port and you can add in online multiplayer with 6 player lobbies, leaderboards and spectator mode, surely making use of the back button isn't some impossible feat.