Leo XIV’s cancer diagnosis upends the pontificate: ‘We thought we had a pope for 20 years; this changes everything in the Curia’

Overnight, the atmosphere at the Vatican has shifted and the future has become more uncertain. The news of Pope Leo XIV’s cancerous tumor has caused devastation, just 17 months after his election in May 2025, at a time when, at 71 and in good physical condition, he was thought likely to remain pope for many years. “We thought we had a pope for 20 years and now it’s no longer clear; this changes everything in the Curia, all the dynamics,” a prelate admits.

No one expected the papacy to enter a phase in which the pontiff was sick or weakened so soon, as in the final years of John Paul II, much of Benedict XVI’s pontificate, or the end of Francis’ tenure. Pending clarification of the exact extent of his illness and the treatment it will require, Leo XIV is already a more fragile figure. “Everything is already in a provisional mode and suddenly the different power groups see they have to reorganize; everything is starting to move,” the same source says.

For now, the Pope’s schedule is suspended until October 20, and the ambitious trip to Uruguay, Argentina, and Peru, scheduled for November 6–17, is up in the air. Leo XIV implied on Sunday, when he announced he would undergo surgery, that the trip remained planned, but after confirmation that the tumor is malignant, everything is now under discussion.

The operation had been scheduled with at least a three-week recovery buffer in mind — the recommended time before safely taking a plane after lung surgery. But other factors now come into play, because the tumor analysis results will not be known for 10 to 14 days and could indicate that the pope will require chemotherapy or radiotherapy.

First doubts in Uruguay and Peru

That will be the decisive moment — between October 23 and 27 — to understand the scenario now opening up and how the pontificate might change, since a pope undergoing demanding treatments will have to ration his work and public presence. In an extreme case of severe debilitation, the question of resignation could be raised again, after Benedict XVI’s precedent when he stepped down in February 2013. In any case, this will strengthen Leo’s inner circle, because he will have to delegate more to them.

To begin with, the fact is that the trip to Latin America, the most imminent engagement, is physically very demanding. Fourteen flights are scheduled in total, more than 40 speeches are programmed, and among the planned visits is Cuzco, in Peru, at over 3,300 meters of altitude where respiratory difficulties can occur. This Wednesday Daniel Sturla, archbishop of Montevideo, admitted for the first time that “it is possible that doctors will not allow him to come now because he may need to undergo treatment, but that he could travel later,” he told Telemundo. Hours later, Peru’s president, Keiko Fujimori, acknowledged that the dates of the pope’s visit could change and that his recovery may “take longer than expected.”

Of course, even if the visit to Latin America does end up taking place, long trips are off the table for now. There were none planned for next year — only one to South Korea, for World Youth Day — and given the current situation, any other plans will be put on hold.

In reality, this changes the entire temporal conception of the pontificate — for the pope, who tends to make plans in the very long term, and for those around him. Leo XIV has been a slow-moving pontiff until now, thinking carefully before each decision because he believed he had a lot of time ahead. Now, depending on the forthcoming diagnosis and treatment, he may have less strength and will have to pick his battles. Others he will simply leave for his successor.

Historically, each pope has calculated his stamina when deciding what he believes he must do, with greater or lesser haste: John XXIII was elected in 1958 at 76, already elderly and of modest health, and was expected to have a short pontificate, yet in just over four years he convened the Second Vatican Council and transformed the Church. He announced those plans three months into his mandate. It will be interesting to see if the illness changes Leo XIV’s governance and accelerates his agenda.

It is also inevitable that the pope will begin to think about succession, with calculated appointments and structural changes that until now had proceeded slowly. For example, his move last Friday is now being viewed in a new light: somewhat unexpectedly, he named Filipino cardinal Luis Antonio Tagle — considered papabile at the last conclave — as the new dean of the College of Cardinals, a key figure during a sede vacante. On Saturday, he also appointed His Holiness’s vicar general for Vatican City — another position that remains in place following the death of a pope. The appointee is the Italian Franciscan archbishop Vittorio Francesco Viola. These are two decisions he made before announcing his upcoming surgery on Sunday, and they make more sense now.

The new situation will also reveal what the Vatican’s transparency and communication policy will now be when it comes to reporting on the pope’s health. This has been changing in recent years, because until John Paul II — the first pontiff to be admitted to a hospital, the Gemelli Polyclinic — it was taboo. The aim was to preserve the almost sacred aura surrounding the figure of the pontiff. With hardly any information available, the death of a pope would come as a surprise. The sudden and controversial death of John Paul I in 1978 — after only 33 days in office — deserves a separate discussion; following his death, it was decided not to perform an autopsy, and there were changes to the official account. In 2025, during Francis’s final weeks in hospital, daily updates were issued, albeit very brief ones.

On this occasion, Francis himself announced his operation from the window of St. Peter’s during the Angelus, a rare gesture of frankness and transparency (John Paul II did the same in 1992 during one of his many admissions to the Gemelli). On the other hand, it has emerged that the Apostolic Palace already knew the tumor was malignant before the surgery, following earlier tests, but it was only announced on Tuesday night after the operation concluded. That revelation is the bombshell that has changed everything. The decision about the trip to Latin America will be the next indicator of the true situation.

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