Pope Leo announced Sunday that he will be having surgery this week to remove a nodule from his lung. He said that the nodule is small, localized, and “was detected at a very early stage.”
The Vatican subsequently said that the pope will have surgery at the Gamelli hospital on Oct. 13, and will spend up to a week at the hospital recovering.
What are the implications of the pope’s announcement? Are lung nodules typically cancerous? And how serious is the surgery he will be undergoing?

The Pillar spoke with Dr. Kristin Collier, clinical associate professor of internal medicine at the University of Michigan, and associate director of the university’s Internal Medicine Residency Training Program.
Collier stressed that she does not have any specific information about Pope Leo’s health situation – and if she did, it would violate ethical standards and patient privacy to discuss it.
However, she said, as an internist, she can discuss pulmonary nodules in general.
The interview is below. It has been edited for length and clarity.
The pope is going to be undergoing surgery tomorrow to remove a “small, localized lung nodule.” What does that mean to you?
When I first read this news report, two questions came to mind — firstly, how was this found? Was he having symptoms that warranted chest imaging of some kind (like a cough for example?). And two, what are the treating physicians concerned about? Because for small lung nodules that have no concerning features, guidelines suggest that these can be monitored with serial imaging tests and only if they grow or develop concerning features, will they then be removed.
So, the nodule must be concerning enough to the treating physicians that they are choosing not to monitor it but resect it instead. This must mean that it is a certain size or has features that are concerning to the treating physicians.
Again, I am not giving a prognosis or diagnosis here but these are the things we consider when deciding to resect vs monitor a lung nodule in general.
Lung nodules are not necessarily cancer, right?
Most lung nodules are not cancer. Lung nodules are very common and prevalence rises with age.
The nodule is localized, and the pope said it was caught early. Does that mean that, if it is cancer, it will be easier to treat?
The “localized” comment means that even if there is concern for a cancer (malignant/cancerous pulmonary nodules can be either from a primary lung cancer, or a metastasis from a secondary cancer somewhere else in the body that has metastasized to the lung) - they don’t see cancer anywhere else in the body.
So, even if this proves to be a nodule that is a cancer of some type, it sounds like that he would be going in for a surgical cure.
The pope is 71 years old, but generally considered to be in good health. Is this a risky surgery? Does it tell you anything that he is expected to remain in the hospital for a week?
This type of surgery is generally considered a low-risk operation. That length of hospital stay is likely just a precaution.
Most of these lung nodules can be removed by a minimally invasive surgical resection, typically video-assisted thoracoscopic surgery (VATS). The surgeon removes the smallest amount of lung that achieves a complete resection, guided by the clinical concern and the size of the nodule — so a wedge of the lung can be removed, or even a larger segment or an entire lobe if there is more concern.
Pope Leo is interrupting a number of events to have this surgery. Is there a reason that this surgery would need to be done urgently?
I can’t comment on why events are being rescheduled — either because they think a delay in surgery would not be in his best interest for some reason (either medical, personal or schedule reasons) or due to the surgeon’s schedule.
Is there anything else that you think is worth noting?
I would be cautious about drawing conclusions about Pope Leo’s individual condition from the limited information publicly available.
I believe physicians have a responsibility to help the public understand medical information accurately, including what we do not yet know. We should avoid turning limited information into a diagnosis or prognosis. That is both a matter of scientific rigor and a matter of respect for the patient.

"I would be cautious about drawing conclusions about Pope Leo’s individual condition from the limited information publicly available."
That may the wisest internet commentary on Pope Leo since his election.
Wise words from a doctor--don't comment about a specific person based on very very limited info. Of course--we pray for the pope and his entire medical team!!