According to the American Cancer Society, lung cancer is the leading cause of cancer death, and it occurs mainly in people 65 and older. Mortality rates have declined in recent years because fewer people smoke than in the past, and because of enhanced lung cancer screening in routine clinical practice for high-risk people. These are people ages 50 to 80 who have smoked at least a pack a day for 20 years, and currently smoke or have quit within the last 15 years.

What are the signs and symptoms of lung cancer?

The most common symptoms are:

  • Worsening cough, including producing blood.

  • Chest pain.

  • Loss of appetite.

  • Weight loss.

  • Shortness of breath.

  • Repeated lung infections that do not respond to antibiotics.

Are all lung cancers the same?

There are two types of lung cancers, which are treated differently based on how advanced they are when they are diagnosed:

  • Non-small cell lung cancer (NSCLC), 80% to 85% of cases.

  • Small cell lung cancer (SCLC), 15% to 20% of cases.

How is lung cancer diagnosed and staged?

Early-stage lung cancers may not produce any symptoms and are detected only when a CT scan of the chest is done in response to other health problems or during screening in high-risk patients.

When a CT scan of the chest shows a suspicious lesion, a biopsy is taken to confirm the type of tumor. Further tests \such as PET-CT scan and MRI of the brain help to place these cancers into stages:

  • Early (stages I-II).

  • Locally advanced (IIIA, can be removed by surgery vs. IIIB, which cannot).

  • Metastatic (stage IV), meaning it has spread to other organs.

Newer methods to detect lung cancer at early stages include fluorescence bronchoscopy and electromagnetic navigation bronchoscopy.

What are the survival rates for early-stage lung cancer?

Early-stage lung cancer is a curable disease with survival rates improving as treatment options advance.

The overall five-year survival rate for patients with NSCLC is 10%-15%, as the majority of patients present with locally advanced disease (stage III) or distant metastases (stage IV). The five-year survival rate is 59% for those who begin treatment while their lung cancer is in stage I or II.

Annual screening with low-dose CT led to a 20% reduction in lung cancer deaths in high-risk patients in a 2011 national lung screening trial.

As of 2018, the lung cancer death rate dropped by 54% for males and by 30% for females since 2002.

This is the first of two parts. Next week: Questions and answers on lung cancer treatments.

Aruna Turaka is a radiation oncologist at Nazareth Hospital in Philadelphia.