He did have a slight worry at one point during the chemotherapy process when he discovered that one of the surgeon's name was "Dr. Abdallah."
"I said to his physician assistant, I said, 'That sounds foreign--not that I had anything against foreign doctors--but it sounded too foreign," Cain tells the audience. "She said, 'He's from Lebanon.' Oh, Lebanon! My mind immediately started thinking, wait a minute, maybe his religious persuasion is different than mine! She could see the look on my face and she said, 'Don't worry, Mr. Cain, he's a Christian from Lebanon.'"
(from http://news.yahoo.com/blogs/ticket/herman-cain-holy-land-experience-130621445.html)