What to know about Pope Leo’s planned lung nodule surgery

VATICAN CITY (AP) — Pope Leo XIV is scheduled to have an operation to remove “a localized nodule” in his lung that was “detected at a very early stage.” It is the first medical event of his 17-month papacy.

Here is what is known:

A lung nodule is a small abnormal area measuring less than 3 centimeters (about 1.2 inches) across. It is sometimes detected on a CT scan performed to investigate another problem, such as trauma or a lung infection, according to the American Cancer Society. Experts say the nodule could be benign or malignant and that prompt evaluation is important.

If the nodule is cancerous and removed at an early stage, the prognosis is “excellent,” and surgery alone may be sufficient treatment, said Dr. Stephen Liu, a lung cancer expert at Georgetown’s Lombardi Comprehensive Cancer Center.

Leo, 71, is considered otherwise healthy and physically fit, both positive factors for his recovery. He said the nodule was discovered during “recent medical tests,” and the Vatican said Monday that no particular health issue prompted the check-up, describing it as “routine.”

The Vatican said Leo will undergo surgery in the first days of this week and is expected to be hospitalized for about a week afterward to recover.

The pope will be treated at Rome’s Gemelli hospital, formally known as the Agostino Gemelli Polyclinic, a private nonprofit Catholic teaching hospital. The facility has a special apartment set up for pontiffs on the 10th floor that includes a private chapel. Leo’s immediate predecessor, Pope Francis, was treated there before his May 2025 death during a long illness prompted by a respiratory crisis.

St. John Paul II spent so much time at Gemelli that he called it “Vatican III,” after the Vatican itself and the papal summer residence at Castel Gandolfo.

Leo has several activities scheduled this week.

In addition to his regular meetings, he is due to celebrate a public Mass on Wednesday to close a weeklong conference on family ministry. Vatican officials suggested on Sunday that he might miss it.

Leo also has a major trip planned Nov. 6-17 to Uruguay, Argentina and Peru . It is unclear whether the surgery and recovery will affect the ambitious itinerary, which includes a dozen flights, two helicopter rides and significant altitude changes in Peru. Leo said earlier in his remarks Sunday that he still planned to make the trip.

The Vatican has no specific rules governing who takes over if a pope becomes totally incapacitated. Even while unconscious during surgery, Leo remains pope and retains his authority.

Pope Francis remained in charge throughout his lengthy hospitalizations, as did St. John Paul II before him. Both made appointments and issued laws and statements from the hospital. A team of officials already handles day-to-day Vatican operations.

Medical advances and popes’ longer lifespans, however, have highlighted this gap in church law and prompted calls for the Vatican to prepare for a pope becoming too ill or incapacitated to govern.

Two days before revealing his planned surgery, Leo confirmed one significant appointment . On Friday, he approved Filipino Cardinal Luis Antonio Tagle as the new dean of the College of Cardinals. Tagle, 69, replaces Cardinal Giovanni Battista Re, 92, whose term Francis extended in the weeks before his death.

The dean plays a significant role in a papal transition . He presides over the previous pope’s funeral and helps lead the cardinals’ closed-door meetings before the conclave to discuss the church’s future needs. If he is under 80 when the conclave begins, he also presides over the secret election of a new pope in the Sistine Chapel.

Barry reported from Milan

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