Former President Jimmy Carter is slated to begin radiation treatment for several melanoma spots on his brain Thursday afternoon, he said at a news conference in Atlanta. Carter, 90, told reporters he had a mass removed from his liver on Aug. 3, which he learned was melanoma. Asked how he felt when he learned of the diagnosis, Carter said: "I just thought I had a few weeks left. But I was surprisingly at ease. I've had a wonderful life, I've had thousands of friends, and I've had an exciting and adventurous and gratifying existence. So I was surprisingly at ease." "I'll be prepared for anything that comes," he added.