Pope Leo XIV has been diagnosed with lung cancer after surgeons removed part of his right lung Tuesday, the Vatican announced.

The 71-year-old pontiff underwent surgery at Agostino Gemelli University Hospital in Rome to remove a small lung nodule that he had publicly revealed just one day earlier. During the operation, doctors confirmed the nodule was lung adenocarcinoma, a form of lung cancer.

The diagnosis was made through an examination of tissue during the surgery and was consistent with findings from tests performed before the procedure, according to the Holy See Press Office.

Surgeons removed the lower lobe of Leo’s right lung using a video-assisted technique. The Vatican said the operation was successful and there were no complications.

Leo spent approximately three hours in the operating room, with the surgery itself lasting about 90 minutes. He awoke normally following the procedure and, after a brief period of observation, returned to his room on the hospital’s 10th floor.

The cancer diagnosis comes one day after Leo told the faithful gathered at St. Peter’s Square that doctors had discovered a small growth in his lung.

“Doctors found a small lump in the lung,” Leo said after Monday’s Angelus address. “It was identified at a very early stage and well situated.”

He said doctors had recommended surgery and asked Christians to keep him in their prayers.

“The doctors consider it appropriate to intervene and so, following their advice, I decided to have surgery to remove it,” Leo said. “The surgery is already scheduled for the next few days. I thank you for your spiritual closeness and I rely on your prayer.”

The diagnosis is an unexpected health challenge for the American-born pope, who has maintained an active lifestyle and had no previously known major health problems. Leo regularly plays tennis and swims while staying at the papal summer retreat in Castel Gandolfo.

Questions now remain about how his recovery could affect his schedule in the coming weeks. Leo is scheduled to embark on a major international trip from Nov. 6 through Nov. 17, with planned stops in Uruguay, Argentina and Peru. The Vatican has not yet announced whether those plans will change.

Even as he prepared for surgery, Leo continued to draw attention to suffering around the world. In his Sunday remarks, he renewed his appeal for peace in Ukraine and warned that the effects of the war extend far beyond the country’s borders.

“The war in the martyred Ukraine continues to create suffering, even beyond its borders, especially in the poorest countries, where many people depend on the exports of cereals and grains,” Leo said.

For now, attention turns to the pope’s recovery following the successful surgery and the cancer diagnosis. Just hours before entering the hospital, Leo had offered a simple request to those following his health: “I rely on your prayer.”