Jeopardy! host Alex Trebek is sharing details about his battle with stage-four pancreatic cancer. In an interview that will air on CBS Sunday Morning, Trebek says that when he first began treatment, he was gripped by terrible stomach cramps at work. “I was on the floor writhing in pain. It went from a 3 to an 11. And I just couldn’t believe, I didn’t know what was happening. And it happened three or four times a day while we were taping,” he said. Trebek, 78, also revealed that his hair fell out because of chemotherapy, so he got a toupee that he thinks is pretty close to the real thing. “On air I’m told that there were times when the hairpiece looked better than my real hair,” he said.