So, apparently Geralt can do something in the expansion that will leave him permanently marked.
Ciri on Geralt Stigma
Geralt Choice: The mark on my face look bad?
Geralt: The mark on my face - is it noticeable? Hard on the eyes?
Ciri: Tsk… a bit. But you can't let it bother you.
Ciri: You know, folk would stare at the scar on my cheek, always. It used to upset me greatly.
Geralt: And?
Ciri: I started undoing one shirt button more. Problem solved.
Triss on Geralt Stigma
Geralt Choice: My mark - help me get rid of it?
Geralt: Listen, think you could help me with this mark? It's driving me crazy.
Triss: Tsk… Oh Geralt… What've you gotten yourself into now?
Geralt: Long story. Can you get rid of this thing?
Triss: Afraid not. And I doubt anyone else'll be able to, either. So sorry.
Geralt: Agh… Folk give me strange looks anyway. Guess I oughta be used to it.
Yennefer on Geralt Stigma
Geralt Choice: This mark - help me get rid of it?
Geralt: Listen… this mark - can you do anything about it?
Yennefer: I can scratch it if it itches, but I fear that's all.
Geralt: I'm not joking, Yen.
Yennefer: Neither am I. These symbols… it's ancient, powerful magic. I've no notion how to remove them.
Geralt: Dammit.
Yennefer: You're still one of the prettiest witchers around in my book. Second only to Lambert.
Source: http://forums.cdprojektred.com/threads/51724-Triss-Merigold-%28all-spoilers%29?p=1881409&viewfull=1#post1881409