Louis Prevost, the older brother of Pope Leo XIV who lives in Florida, has multiple myeloma, his wife told CBS News on Tuesday. The news comes amid the Vatican’s earlier announcement that the Pope has been diagnosed with lung cancer after undergoing surgery to remove the lower lobe of his right lung. Deborah Prevost did not share what stage Louis’ cancer is at, but said he is currently in a clinical trial at a local hospital where he is being treated. Multiple myeloma is a type of cancer that affects plasma cells, according to the Multiple Myeloma Research Foundation. Deborah Prevost said Louis was first diagnosed in 2017, but was able to keep it at a “very low level” after undergoing treatment in 2019 that included stem cell treatment and a clinical trial. “He came out of remission” three months ago, he said. She could not comment on the specific details of Pope Leo’s condition, but said her husband and brother spoke last week before Louis entered his clinical trial. “He called to let us know what was going to happen,” Deborah said. “We continue to pray, keeping our spirits high for both of us.” Pope Leo underwent surgery Tuesday that confirmed he has lung cancer, the Vatican said Tuesday. The Vatican did not reveal what stage the cancer was or whether it may have spread. He also did not detail what additional procedures the Pope might have to undergo. Deborah Prevost told CBS News that the family was “going through a lot,” but she was hopeful that Leo’s cancer was in the early stages. He said he had not heard of any possible radiation or chemotherapy treatments. In an interview with CBS News in May 2025, after then-Cardinal Robert Prevost was elected the new pope, Louis Prevost said the family knew that “from a very young age, there was something special about Rob.” Pope Leo is the first American-born leader of the Catholic Church. He grew up with his two older brothers, Louis and John, in the Chicago area. “While I was playing kid’s games, you know, whether it was baseball, cops and robbers, tag, flashlight, any kid’s game, Rob liked to play priest,” Louis Prevost told CBS News at the time. “Ever since then, he’s had that calling.” “He will always be Rob,” Louis added. “If we get there and meet him, I’ll still treat him like my little brother. Give him a hug and say, ‘Rob, you idiot, what have you done?’ Take his hat off and give him a nuggie.” Faris Tanyos, Kierra Frazier and The Associated Press contributed to this report. Pope Leo XIV: The First American Pope Go Deeper with The Free Press In:
