Definition

Lung cancer is a disease in which cancer cells grow in the lungs. The most common type of lung cancer are:

• Non-small cell lung cancer—generally grows and spreads more slowly (most common)
• Small cell lung cancer—generally grows more quickly and is more likely to spread to other parts of the body

Lung Cancer Copyright © Nucleus Medical Media, Inc.

Causes

Cancer occurs when cells in the body divide without control or order. If cells keep dividing when new cells are not needed, a mass of tissue forms. This growth is called a tumor. Cancer growths can invade nearby tissue. It can then spread to other parts of the body. Regular damage increases the turnover of cells.

The following are known to damage to the lungs, and cause lung cancer:

• First- or second-hand smoke from cigarettes, cigars, or pipes
• Exposure to asbestos (a type of mineral) or radon (radioactive gas)

Risk Factors

Things that may increase your chances of lung cancer are:

• Smoking
• Using chewing tobacco
• Exposure to second-hand smoke
• Exposure to asbestos or radon
• Having a lung disease, such as tuberculosis
• Family or personal history of lung cancer
• Exposure to certain air pollutants
• Exposure to coal dust
• Radiation therapy that was used to treat other cancers
• HIV infection

Symptoms

Symptoms and signs may include:

• A cough that does not go away and worsens over time
• Constant chest pain
• Coughing up blood
• Shortness of breath, wheezing, or hoarseness
• Repeated problems with pneumonia or bronchitis
• Swelling of the neck and face
• Loss of appetite or weight loss
• Fatigue
• Clubbing—tips of fingers and toes become wider and rounder

Diagnosis

The doctor will ask about symptoms and past health. A physical exam will be done. The doctor will also ask about:

• Smoking habits past or present
• Things you may have come in contact with that can harm lungs
• Family history of cancer

Tests may include:

• Sputum cytology—mucus from the lungs is sent to a lab
• Biopsy—a sample of lung tissue is removed and looked at under a microscope

Images of the lungs and chest may be taken with:

• Chest x-ray
• CT scan of chest
• PET scan
• PET/CT scan
• Bone scan

The doctor will use results from all tests to determine the stage of cancer. Staging is used to guide your treatment plan. Lung cancer is staged from 1 to 4. Stage 1 cancer is contained in a small area. Stage 4 caner is one that has spread to other parts of the body.

Lung cancer screening may also be recommended to long-term smokers. These tests can help to find earl stage cancer in those at high risk.

Treatment

The goal of treatment is to remove as much cancer as possible and control the symptoms.

Prevention

To help reduce your chances of lung cancer:

• Do not start smoking. If you smoke, talk to your doctor about how to successfully quit.
• Avoid places where people are smoking.
• Test your home for radon gases and asbestos. Have these substances removed if they are in the home.
• Try to avoid or limit occupational exposures.

The American Lung Association and American Cancer Society both suggest that screening for lung cancer with a low-dose CT scan may be considered if you are a smoker (or former smoker), aged 55 to 74 years, and have a history of heavy smoking.