What is Lung Cancer?

Cancer is caused by malignant (cancerous) cells that grow and multiply without control. When cancer begins in any part of the lungs, it is called lung cancer.

The two basic types of lung cancer are named for how large the cancer cells appear when viewed under a microscope:

  • Non-small cell lung cancer accounts for most lung cancer cases (about 85 to 90%), according to the American Cancer Society (ACS). It grows and spreads quickly to other organs.
  • Small cell lung cancer accounts for fewer lung cancer cases (about 10 to 15%), according to the ACS.

The ACS estimated that about 234,030 new cases of lung cancer (both non-small cell and small cell) would be diagnosed in the United States in 2018. It is important to remember that great strides have been made in our understanding of lung cancer. Ways to treat lung cancer have advanced even from just a few years ago, changing the landscape of treatment options and outlook (prognosis).

Lung Cancer Symptoms

A cough that does not go away is the most common lung cancer symptom. Symptoms depend on if the cancer is localized or if/where it has spread. Other symptoms include:

  • Chest pain
  • Shortness of breath
  • Wheezing
  • Bloody or rust-colored sputum (a mixture of saliva and mucus coughed up from the lungs)
  • Hoarseness
  • Swelling of the neck and face
  • Weakness in the shoulder, arm or hand
  • Feeling tired
  • Loss of appetite or unintentional weight loss
  • Fever
  • Night sweats

The symptoms of lung cancer may look like symptoms of other medical conditions.

Diagnosing Lung Cancer

The first step in diagnosing any disease is to complete a medical history and physical exam. In order to diagnose lung cancer, your doctor may also order tests and procedures such as:

  • X-rays: These images can show any mass or spot on the lungs that might be cancer.
  • Computed tomography (CT) scan: A series of X-ray images of inside the body are combined to produce cross-sectional views of the lung. This test can show a tumor along with its spread elsewhere in the body.
  • Positron Emission Tomography (PET) scan: A PET scan uses a special dye that allows doctors to see how the body tissues are working and what they look like. This test can show whether a tumor has spread elsewhere in the body.
  • Magnetic Resonance Imaging (MRI) scan: An MRI scan uses strong magnetic fields and radio waves to capture detailed images of organs and tissues in the body. MRIs are very useful for imaging the brain and spinal cord.
  • Biopsy: A small sample of tissue or fluid is removed from the lung. A pathologist then views it under a microscope to check for cancer. Biopsies are vital for obtain cancerous tissue for genetic testing. A biopsy may be done by methods such as:
    • Fine needle aspiration biopsy: A thin, hollow needle is used to remove tissue or fluid from the lung
    • Thoracentesis: A hollow needle is inserted into the chest wall to remove fluid
    • Bronchoscopy: A flexible tube called a bronchoscope is passed down through the nose or mouth and into the bronchi to remove tissue
    • Mediastinoscopy and thoracoscopy: With both of these procedures, a thin, tube-shaped instrument is inserted into the chest to obtain tissue or lymph node samples.

Staging Lung Cancer

These tests and procedures can also help your doctor determine the stage of lung cancer. Staging is a way of describing how much the cancer has grown, how big it is and whether it has spread to other parts of the body. Staging is important because it helps your doctor plan your treatment and determine your outlook (prognosis). Lung cancer has 4 stages, numbered from 1 to 4.

  • Stage 1 means that the cancer is relatively small and contained within the lung.
  • Stages 2 and 3 mean that the cancer is larger than stages 1 and 2 and may have spread into lymph nodes and surrounding tissues close to the tumor.
  • Stage 4 means that the cancer has spread to the lung lining, the opposite lung, or another body organ. This is also called metastatic cancer.

Learn about the stages of non-small cell lung cancer and the stages of small cell lung cancer on the National Cancer Institute website.

Treating Lung Cancer

If you are diagnosed with lung cancer, your care team will work with you to develop a treatment plan that is right for you. This plan will depend on the type and stage of your cancer, your general health, and your treatment preferences.

Lung Surgery

Lung cancer surgery may involve removal of a tumor and some nearby healthy tissue, part of a bronchus, an entire lobe (section) of a lung or an entire lung. Chemotherapy or radiation therapy may also be used to kill any cancer cells left behind.

  • Sleeve resection: Part of a bronchus, the main airways of the lungs
  • Wedge resection: A tumor and some nearby healthy tissue
  • Lobectomy: An entire section of a lung
  • Pneumonectomy: An entire lung

Non-surgical Lung Cancer Treatments

Other common treatment options for lung cancer include the following:

  • Immunotherapy helps your immune system fight cancer. The immune system helps your body fight infections and other diseases. It is made up of white blood cells and organs and tissues that are part of the lymph system. Some types of immunotherapy are also sometimes called biologic therapy or biotherapy.
  • Chemotherapy kills cancer cells through the use of intravenous (IV) or oral drugs.
  • Targeted therapy uses drugs that attack specific parts of cancer cells, depending on if you have a genetic mutation and what type of mutation it is. These drugs work differently from standard chemotherapy drugs.
  • Radiation therapy uses high-energy radiation beams to kill or shrink a tumor while sparing healthy tissue. The radiation source can come from outside the body (external radiation therapy) or from implants inside the body (internal radiation therapy).
  • Clinical trials may provide access to new and promising therapies for lung cancer.