Pope Leo to have surgery for lung nodule: What you need to know

Pope Leo, 71, will undergo surgery in the coming days to remove a lung nodule that was detected during a routine check‑up. The growth, described by the Pope as “well contained” and spotted early, is no more than 3 centimetres in diameter, the threshold that distinguishes a nodule from a larger mass.

Lung nodules are small growths found in the spongy tissue of the lungs. They are usually detected by chest imaging, often using an X‑ray or a computed tomography (CT) scan, and many are discovered incidentally on scans performed for unrelated reasons. In the United States, nodules appear in about 31 % of chest CT scans. A Dutch study of 10 431 never‑ or former‑smokers found nodules in 37.7 % of women and 47.5 % of men, while the Australian National Lung Screening program estimates that up to half of all people screened will have a nodule, most of which are neither symptomatic nor cancer‑related.

Older age, smoking, a family history of lung cancer, and asbestos exposure increase the likelihood of developing a nodule. Roughly 95 % of nodules are benign, caused by infections, immune‑related diseases, or genetic abnormalities. In rare cases—between 3.7 % and 5.5 %—a nodule may represent an early stage of lung cancer. Clinicians assess risk by considering size, density, location, and patient factors such as age and smoking history, and they may review previous imaging to detect changes.

If a nodule is symptomatic, rapidly growing, or judged high‑risk, it may be removed surgically. Open‑lung surgery involves an incision between the ribs, while minimally invasive procedures use smaller chest incisions, a camera, and sometimes robotic assistance. After removal, if the nodule is cancerous, follow‑up treatment aims to prevent spread. Recurrence risk for early‑stage, non‑small‑cell lung cancer is 6–10 % in the first four years and then drops to about 2 % per year; the risk of a new lung cancer remains 3–6 % and does not change over time, compared with a 0.055 % annual risk in the general population.