Pope Leo cancer diagnosis: What is lung adenocarcinoma, symptoms, treatments & who are at risk

Pope Leo has been diagnosed with lung adenocarcinoma, a common form of lung cancer. Surgeons removed the lower lobe of his right lung on Tuesday, the Vatican said. The disease develops in cells lining the lungs’ air sacs and can be tough to detect during early stages because it often causes no symptoms. Although smoking is the leading risk factor, the cancer also occurs frequently among people who have never smoked. Surgery offers the best chance of a cure when the tumour is confined to the lung, while treatment options for other cases include chemotherapy, radiotherapy and newer drug therapies. The Vatican has not disclosed the tumour’s size, whether cancer has reached nearby lymph nodes or what further treatment the Pope may require. These details are crucial in determining his prognosis, as survival rates vary significantly depending on how far the disease has spread.

What is lung adenocarcinoma?

Adenocarcinoma originates in glandular cells, which produce substances such as mucus. In the lungs, it is the most common subtype of non-small cell lung cancer (NSCLC), which accounts for approximately 80%-85% of all lung cancer cases.

According to the Lung Cancer Foundation of America, adenocarcinoma makes up roughly 40% of lung cancer cases. It generally develops in the outer regions of the lungs and tends to grow more slowly than some other lung cancers, potentially allowing doctors to detect it before it spreads.


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Who is at risk?

Smoking is the primary risk factor for lung adenocarcinoma. However, it is also the most common type of lung cancer diagnosed in people who have never smoked. The Pope is not known to have smoked.

What are the symptoms?

Early-stage lung adenocarcinoma may not produce noticeable symptoms and can be discovered during scans conducted for unrelated medical reasons.

As the disease advances, patients may experience a persistent cough, breathing difficulties, wheezing, coughing up blood, chest, shoulder or back pain, unexplained weight loss and fatigue.

The Vatican said the tumour was detected during a routine health examination. On Sunday, Leo indicated that the growth was well-contained and had been identified early.

How is it treated?

Surgery provides the strongest chance of a cure when cancer remains confined to the lung. A common procedure is a lobectomy, which involves removing an entire lobe of the lung, as in the Pope’s operation on Tuesday.

The procedure is generally preferred when the tumour is restricted to one lobe because it aims to remove the cancerous tissue while retaining as much lung function as possible.

Depending on the cancer’s stage, doctors may also recommend chemotherapy, radiotherapy, targeted drugs or immunotherapy. The Vatican has yet to clarify whether Leo will require additional treatment.

What is the prognosis?

It depends largely on whether the cancer has spread beyond the lung. Since the Vatican has not released details about the tumour’s size or lymph node involvement, Leo’s individual prognosis cannot yet be assessed.

The American Cancer Society puts the five-year relative survival rate for non-small cell lung cancer at 67% when the disease is confined to the lung. This falls to around 40% if it reaches nearby tissues or lymph nodes and approximately 12% if it spreads to distant organs.

Prognosis also depends on tumour size, lymph node involvement, age and overall health.