Pope Leo has been diagnosed with lung cancer following surgery to remove part of his right lung, the Vatican has announced.
The 71-year-old pontiff has lung adenocarcinoma, a common form of cancer, with tissue tests conducted during the operation confirming doctors’ suspicions from earlier examinations, according to a medical bulletin issued by the Vatican.
Leo was admitted to Rome’s Gemelli Hospital on Tuesday for surgery to remove a growth discovered during a recent routine medical check.
The pope’s lead surgeon, Dr Stefano Margaritora, and personal physician, Dr Luigi Carbone, said the procedure lasted about 90 minutes and was successful, with no complications.
“In order to make the procedure curative, the lower lobe of the right lung was removed using a video-assisted technique,” they said, explaining that the aim was to eliminate all cancerous tissue.
However, the stage of the cancer remains unknown, as the Vatican has not provided details about the size of the tumour or whether it has spread to the lymph nodes.
Dr Stephen Liu, a lung cancer expert at Georgetown University in Washington and division chief of haematology-oncology at MedStar Georgetown University Hospital, said more information was needed to assess the pope’s condition.
“While we have the diagnosis, we do not yet have the stage. This is critical to prognosis and treatment,” Liu told Reuters.
“If this is a small lung cancer with no lymph nodes involved, surgery itself is likely to be curative,” he said.
“But if final analysis reveals a greater extent of cancer involvement, this indicates a poorer prognosis.”
The Vatican said Leo regained consciousness normally after the operation and returned to his hospital room, where he was resting.
Earlier in the week, the Vatican said the pope was expected to remain in hospital for about a week. All his public engagements have been cancelled until October 20.
Leo left the Vatican shortly before 1 p.m. on Tuesday and travelled about nine kilometres to Gemelli Hospital.
Elected by the world’s cardinals in May 2025, Leo is relatively young for a Church leader. He enjoys sports, including tennis, and is not known to be a smoker or to have experienced recent health problems.
The pope is scheduled to undertake an 11-day tour of Uruguay, Argentina and Peru from November 6 to 17, although it remains unclear whether the trip will proceed as planned.
Born Robert Prevost in Chicago in 1955, Leo spent decades as a missionary and bishop in Peru before becoming pope.
In 1985, while serving as a young priest in Chulucanas, Peru, he contracted typhoid fever and was hospitalised. Recounting the experience in a book published by Penguin Peru, he said the pain was so severe that he asked God to let him die rather than continue suffering.
He interpreted his survival as a sign from God that “We need you here (on Earth),” he said.
“I never looked back,” Leo added.
His predecessor, Pope Francis, died aged 88 in April 2025 after several hospitalisations in his later years.
