With the cure of the negative effects of Corpus in the main quest does that mean that Yagrum Bagarn (and the rest of the infected at the Corprusarium) would lose the growths if he was cured?

Probably, but I don't think Fyr would give Yagrum the antidote until he was sure it wouldn't kill him.

You should always do a search before asking a question. As shown in a very http://www.gamesas.com/bgsforums/index.php?showtopic=1020951&hl=corpus, the cure only seemed to work on the divinely-chosen Nerevarine and no other.

In addition, it seemed like the nerevarine got cured during the early stages of corpus instead of it being full blown corpus disease, which includes everyone in the corpsimarium and the dwemer.

However, for the OP, the Yagrum has noted that he has been experimented on repeatedly, and his current situation is that he's not getting better, but he's not getting any worse.