It often takes a chest X-ray or CT scan to spot small lung (or pulmonary) nodules, especially when a patient is asymptomatic.

At less than 3 centimeters (1.1 inches), lung nodules are less likely to press against your airway and cause any chest pain or shortness of breath or wheezing.

In the case of Pope Leo XIV , who told a gathering at the Vatican on October 11, 2026, doctors had found a nodule on his lung, it is unclear exactly how large that nodule is.

What we know so far

All we know (at time of writing on October 12, 2026) is that it was "detected at a very early stage," and that it was "well localized."

That suggests it has not spread or metastasized, although its full status is not publicly known.…