Updated January 06, 2015.

Written or reviewed by a board-certified physician. See About.com's Medical Review Board.

Stage 4 non-small cell lung cancer (metastatic lung cancer) is the most advanced stage of lung cancer. Nearly 40% of people newly diagnosed with lung cancer already have stage 4 disease. This stage of lung cancer is not curable, but it is treatable, and many clinical trials are in progress looking at new treatments to improve survival.

Definition

Stage 4 non-small cell lung cancer defines a lung tumor of any size that has spread (metastasized) to another region of the body, to another lobe of the lungs, or is accompanied by a malignant pleural effusion.

Symptoms

These may include
Symptoms due to the presence of a tumor in the lungs such as:

• Persistent cough
• Coughing up blood (hemoptysis)
• Shortness of breath
• Hoarseness
• Pain the chest, back, shoulder or arms
• Repeated episodes of pneumonia or bronchitis
• Wheezing

Symptoms due to spread of the tumor to other regions of the body, for example:

• Pain in the back, hips, or ribs if the tumor has spread to bone
• Difficulty swallowing due to a tumor being near or invading the esophagus
• Headaches, vision changes, weakness, or seizures if a tumor spreads to the brain
• Jaundice (a yellowing of the skin) from tumor that has spread to the liver

And symptoms related to metastatic cancer in general:

• Fatigue
• Unintentional weight loss
• Loss of appetite

Treatment

Because stage 4 lung cancer has spread beyond the lungs it is considered inoperable, that is, surgery would be unable to remove all of the tumor and offer a chance for a cure. But stage 4 lung cancer is treatable. In those that are able to tolerate chemotherapy, traditional chemotherapy, immunotherapy, and/or the newer targeted therapies may improve survival and help with the symptoms of lung cancer.

Many clinical trials are in progress looking at new targeted therapies, combinations of chemotherapy and targeted therapies and also immunotherapy.”

Radiation therapy may be recommended as a palliative therapy –- therapy that is done to control symptoms but does not result in a cure. This can be helpful for some people to control bone pain (due to tumors spreading to bone), bleeding from the lungs, tumors that are obstructing the airways and causing shortness of breath, or brain metastases that are causing significant symptoms, such as headaches or weakness.

It's now recommended that all patients with advanced lung adenocarcinoma and some people with squamous cell carcinoma of the lungs should have genetic testing (molecular profiling) done on their tumor.  For a subset of people with EGFR or ALK mutations, medications are available that can increase progression-free survival.

It is important to discuss any treatment you are considering with your doctor and your loved ones, so you can carefully weigh the risks and benefits of treatment.

• Chemotherapy for Lung Cancer
• Radiation Therapy for Lung Cancer
• Clinical Trials for Lung Cancer

Prognosis

The overall 5-year survival rate for stage 4 lung cancer is sadly only around 1%.  The median survival time (time at which 50% of patients are alive and 50% have passed away) is about 8 months.

• What is Stage 4 Lung Cancer Life Expectancy?
• Where Does Lung Cancer Spread?
• Lung Cancer Survival Rates by Type and Stage

What Can I Do to Help Myself?

Studies suggest that learning what you can about your lung cancer can improve your quality of life, and possibly even your outcome. Ask questions. Learn about clinical trials. Consider joining a support group. Many of us hesitate to talk about end-of-life issues, but discussing these with your doctor and your family –- even if all of you are hoping for a cure –- is associated with fewer feelings of loneliness and a better quality of life. Never lose hope, even if you have chosen not to pursue further treatment. Hope for quality time with loved ones, with good control of your symptoms. Hope for the future of your loved ones who will remain, with memories of you in their hearts.

• How to Find a Lung Cancer Support Group
• Tips for Improving Lung Cancer Survival

Further Reading

• Supporting a Loved One With Cancer
• What Can You Expect During the Final Stages of Lung Cancer?
• Coping With Lung Cancer

<sub>Sources:

American Cancer Society. Cancer Facts and Figures 2014. Atlanta: American Cancer Society; 2014. http://www.cancer.org/acs/groups/content/@research/documents/webcontent/acspc-042151.pdf

American Cancer Society. Lung Cancer (Non-Small Cell.) Non-Small Cell Lung Cancer Survival Rates by Stage. 12/12/2014. http://www.cancer.org/cancer/lungcancer-non-smallcell/detailedguide/non-small-cell-lung-cancer-survival-rates

American Joint Committee on Cancer. Lung Cancer Staging. 7th Edition. Accessed 09/20/14. https://cancerstaging.org/references-tools/quickreferences/Documents/LungMedium.pdf

Edge, S. et al (Eds.). AJCC Cancer Staging Manual. 7th Edition. Springer. New York, NY. 2010.

Faithi, A. and J. Brahmer. Chemotherapy for advanced stage non-small cell lung cancer. Seminars in Thoracic and Cardiovascular Surgery. 2008. 20(3):210-6.

Labadede, O. et al. TNM Staging of Lung Cancer – A Quick Reference Chart. Chest. 1999. 115(1):233-235.

National Cancer Institute. Non-Small Cell Lung Cancer (PDQ). Stage IV Non-Small Cell Lung Cancer. 08/16/14. http://www.cancer.gov/cancertopics/pdq/treatment/non-small-cell-lung/HealthProfessional/page12.

Socinski, M. et al. Treatment of Non-small Cell Lung Cancer – Stage IV: AACP Evidence-Based Clinical Practice Guidelines. Chest. 2007. 132(3 Suppl):277S-289S.</sub>