Hey satman.
My understanding, even as recent as yesterday in speaking with my AN treatment team, that potential regrowths can occur with any AN patient, regardless of type of treatment they have for their AN's. These schwann cells that AN's are comprised can be terrible buggers when they form an AN.. and one reason why, as AN'ers, we should maintain head MRI follow-ups down the road, even post treatment, to make sure there are no others that decide to crop up. My dr (yesterday) reminded me that the chances are slim, but the chances are there and that is part of the AN reality. I don't allow it to be foremost in my mind... I keep it tucked away, knowing... there are slim chances of it occurring, but yes, for some, it can. I know of some that had regrowths (many that participate here on the forums)... and I try not to allow it to consume my thoughts.
Hoping this answer helps.
Phyl