Blizzard have found and fixed a bug with Outlaw Rogues that was allowing them to do some very high DPS. Runs with that exploit will be removed and it seems some bans or at least suspensions might be coming as well!
As of a few hours ago today (October 24), we corrected a bug that allowed Outlaw Rogues to contrive conditions in which they could do very high damage.
We are now working on removing clearly exploited runs from leaderboards and taking account actions where appropriate.
Thank you to all who reported this.