(Reuters) – Former U.S. President Jimmy Carter said yesterday that he will no longer need treatment for melanoma, a type of skin cancer that had spread to his liver and brain, a spokeswoman said. The 91-year-old Nobel Peace Prize winner will continue to be observed by doctors, but will not need treatment with a promising immunotherapy drug that helps the body’s immune system target cancer cells, said Deanna Congileo, spokeswoman for his nonprofit public policy center, the Carter Center. Congileo told Reuters in an email that if doctors find that the former president’s cancer returns, he will resume treatment at Emory University’s Winship Cancer Institute, where he received radiation and immunotherapy treatment from August 2015 through February, 2016