Non-Small Cell Lung Cancer

Lung cancers can be divided into 2 main types: non-small cell lung cancer (NSCLC) and small cell lung cancer. NSCLC is more common. About 85 percent of people with lung cancer have NSCLC.^1,2

What is NSCLC?

The type of lung cancer is determined by looking at the cancer cells under a microscope. In small cell lung cancer, the cancer cells look small under the microscope. In NSCLC, the cancer cells are bigger.²

Types of NSCLC

NSCLC develops in the tissues of the lung. There are different types of NSCLC. They all develop in the tissues of the lung. But they begin in different parts of the lungs. And each type grows and spreads in different ways.^1,2

The 3 main types of NSCLC are:^1,2

• Adenocarcinoma
• Squamous cell carcinoma
• Large cell carcinoma

Adenocarcinoma

Adenocarcinoma is the most common type of NSCLC. About half of the people diagnosed with lung cancer have adenocarcinoma.^1-3

Adenocarcinoma usually develops near the outer edges of the lungs. It starts in the cells that line the lungs and make mucus. This type of NSCLC is common whether or not you have a history of smoking. It is also more likely than other types of NSCLC to occur in younger people.^1-3

Squamous cell carcinoma

Squamous cell carcinoma starts in the squamous cells. These are flat cells in the tissue that lines your airways. This type of NSCLC is usually found in the central parts of the lungs where the airways connect to the lungs. But it is also possible to find it near the edges of the lungs. Squamous cell carcinoma is often linked to a history of smoking.^1-3

Large cell carcinoma

The other main type of NSCLC is large cell carcinoma. Your doctor may diagnose large cell carcinoma if the appearance of your NSCLC does not fit into adenocarcinoma or squamous cell carcinoma. This type of NSCLC can start in any part of the lungs. It can grow and spread quickly, making it more difficult to treat.^1,2

Less common types of NSCLC

There are other types of NSCLC which are much less common. These include:^1-4

• Adenosquamous carcinoma
• Sarcomatoid carcinoma
• Salivary gland carcinoma
• Non-small cell neuroendocrine tumors

Risk factors

Smoking is the biggest cause of lung cancer. About 90 percent of all lung cancer cases are caused by smoking tobacco. Other risk factors include:^1,4

• Second-hand smoke
• Drinking alcohol
• Air pollution
• Inhaling harmful substances like asbestos, radon, or arsenic
• Radiation therapy
• Old age
• Having family history of lung cancer

Certain illnesses can also increase your risk of developing NSCLC. These include:^1,2

• Chronic obstructive pulmonary disease, also known as COPD
• Pulmonary fibrosis
• HIV

Symptoms

Symptoms of NSCLC include:^1-4

• Cough, shortness of breath, difficulty breathing
• Difficulty swallowing
• Swelling in the face or neck
• Chest pain
• Loss of appetite
• Weight loss
• Coughing up blood

NSCLC can also spread to other parts of the body. This can cause more symptoms depending on where the cancer spreads. Places NSCLC may spread include your bones and brain.^1,2

Diagnosis

Your doctor may think you have NSCLC based on your symptoms, health history, and physical exam. If your doctor suspects NSCLC, they will typically use the following tests to confirm the diagnosis:^1,2

• Blood tests – Specific blood tests are used to look for any markers or imbalances that can be caused by NSCLC.
• Imaging tests – Chest X-rays and CT (computed tomography) scans can be used to see if lung cancer is present.
• Biopsy – A piece of tissue from the lungs is removed to look under a microscope. This is used to find out which type of lung cancer is present.

Your doctor may also need more tests to find out if the cancer has spread to other parts of your body.⁴

Treatment

Your doctor will create a treatment plan based on the type of NSCLC that is present. Treatment options may include:^1,2

• Chemotherapy
• Radiation therapy
• Surgery
• Targeted therapy
• Immunotherapy (drugs that help your own immune system fight cancer cells)