A few years ago, my father-in-law had brain cancer, and he's actually had surgery twice on it. And he's doing just fine now. In fact, after the last surgery, he was up and walking in just a few days and back to work within weeks.
And this summer, my wife had a non-cancerous tumor in her head, and we had it removed and she was up and walking within a few days. After just a few weeks, she's doing really good.
My FIL had surgery a few years ago and then again last Christmas. In just those few short years, the quality and expertise of the surgeons has increased greatly. That's maybe why he recovered so quickly after the second one. And my wife was out of the hospitals within days. So if people give you horror stories of brain surgery from the 80's and early 90's, don't listen to those.
I'm assuming your brother is younger, so that only helps him immensely. I'll pray for both your brother, you, and your family.
Also, be careful cubing around him afterwards, since the clicking will really really drive him crazy, but he might be too tired to complain.
