The system requirements are the same for 2K11 & 12. If you were able to run 11 on med, I believe 2K12 will run on medium settings as well. The game is developed for consoles first, then ported to the PC.
Console hardware does not change, so 2K12 does not need PC players to make a hardware upgrade to run the game at the same settings. Developers just learn how to optimize the performance on the programming side. Anyway, you should be able run it.

Comment