This page was reviewed under our medical and editorial policy by
Maurie Markman, MD, President, Medicine & Science
This page was updated on September 12, 2022.
Like other types of cancer, lung cancer is categorized by stages based on how widespread it is in the body. In general, the higher the stage, the more severe the cancer.
Stage 4 lung cancer, also called metastatic lung cancer, is an advanced disease. In stage 4 lung cancer, the cancer has spread from the lung, where it originated, to other parts of the body.
Metastasis occurs when cancer cells separate from the original tumor and move through the body via the blood or lymph system. The cancer cells often travel from the lung to the brain, bones, liver and adrenal glands where they may form new metastatic tumors. At that point, any metastatic tumors that develop in another area of the body are still considered lung cancer, because they are made up of lung cancer cells.
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Sometimes, advanced lung cancer is discovered due to symptoms. The following lung cancer symptoms may accompany any stage, although they’re more likely to occur as the cancer progresses:
Other symptoms that may develop as a result of the lung cancer metastasizing to other parts of the body include:
These symptoms may be caused by a less serious condition. Still, it’s important to visit a doctor to evaluate these symptoms, because many are serious, and a doctor may help determine what is causing them.
Doctors use various tests, procedures and scans to look for lung cancer. They can be used to detect cancer signs, verify a diagnosis if cancer is suspected or determine the cancer's stage.
Advanced or metastatic lung cancer may be diagnosed through these procedures:
Non-small cell lung cancer (NSCLC) is one of two major types of lung cancer, and the more common.
NSCLC stages, which range from stage 1 to stage 4, are determined based on several factors, including the main lung tumor’s size and whether the cancer has spread to lymph nodes near the lungs or metastasized farther away in the body.
In stage 4, NSCLC is metastatic, meaning that it has spread beyond the lung where it began. Depending on how extensively it has spread, stage 4 NSCLC is further divided into two substages: 4A and 4B.
Non-small cell lung cancer stage 4A: In stage 4A, the tumor may vary in size, and it may or may not have spread to the lymph nodes. One (or more) of these may also be the case:
Non-small cell lung cancer stage 4B: In stage 4B, the cancer is widespread, in multiple places or organs far away from the lung.
While cancers that fall into either of these substages may be referred to as stage 4, they may require different treatments. Stage 4B is more common, but it’s generally more difficult to treat and has a lower chance of survival.
The second most-common type of lung cancer after NSCLC is small cell lung cancer (SCLC). SCLC is not typically grouped into numbered stages. Instead, it’s identified as limited stage or extensive stage.
Treating metastatic lung cancer is challenging. This stage of cancer may continue to spread, and small bits of the disease may linger in the body and cause a recurrence, even if the treatment appears successful. Therefore, treatment will typically focus on extending and bettering life by relieving symptoms and controlling the cancer's growth. A few things to consider:
Treatment options for metastatic lung cancer may vary depending on factors such as:
Stage 4 NSCLC treatment may include:
If the cancer has metastasized to one other site—particularly the brain—a typical course of treatment may begin with surgery and radiation therapy to target the area where the cancer spread. Then, the focus shifts to the lung, where treatment may include some combination of surgery, chemotherapy and radiation (depending on the specifics of the tumor).
More often, though, cancers at this stage may be too widespread and require systemic treatments that attack the cancer throughout the body.
The first consideration in choosing a systemic treatment is whether there are specific genetic changes in the primary lung tumor that may be targeted. If so, targeted therapy drugs designed to act on these gene changes would likely be the first choice. Chemotherapy, immunotherapy, or both, also may be options.
Because extensive-stage SCLC is cancer that has spread extensively in the body, systemic treatments (such as chemotherapy or immunotherapy) would be more useful than therapies (such as radiation therapy or surgery) that target a specific region of the body. As with stage 4 NSCLC, treatment would likely focus on blocking the cancer's growth, relieving symptoms and extending the patient's life. Chemotherapy and immunotherapy, or a combination of both, are typically the first line of treatment at this stage.
Patients with advanced lung cancer typically receive palliative care, whether alongside other treatments or on its own (if the patient has chosen not to pursue standard treatment).
Palliative care is intended to improve the quality of life for patients with serious conditions by focusing on treating emotional and physical symptoms. This approach emphasizes the patient and his or her needs over targeting the disease itself.
Palliative care is not the same thing as hospice, and may be beneficial for patients dealing with a severe illness—at any stage. Joining support groups or speaking with a counselor may also be helpful.
In some cases, if a patient's health is quickly declining, standard treatments may be too taxing on the body and lead to debilitating side effects. If this is true, ask a doctor about lowering the treatment doses or receiving palliative care on its own.
Lung cancer becomes more serious and difficult to treat as it progresses. Advanced or metastatic lung cancers of any kind tend to have very low survival rates.
One way to estimate life expectancy when battling cancer is to consider the five-year relative survival rate for that type of cancer. A five-year relative survival rate shows the likelihood that a person with a specific type and stage of cancer would live for at least five years after the diagnosis, compared with people who don't have cancer. The rate includes the life expectancy of patients who are still in treatment and those who have finished treatment and have no further evidence of disease.
It's important to remember that these rates are based on patients who had advanced lung cancer at least five or more years ago, and the rates may not account for recent advances in treatment options. The rates also don't consider all factors specific to each individual, such as the type of cancer and the care he or she is receiving.
At City of Hope, our lung cancer centers bring together multidisciplinary teams of doctors and other clinicians with the expertise to treat all stages of the disease, including stage 4 lung cancer. The experts at our lung cancer centers collaborate daily, delivering personalized treatments tailored to each patient’s needs and goals.
Stage 4 lung cancer is a complex disease. At City of Hope, our lung cancer doctors and other clinicians are committed to helping you understand the challenges that come with a stage 4 lung cancer diagnosis, so you can make informed decisions about your care.
"When I was diagnosed, my niece was expecting her first child. Five years later, I was there to see this child start kindergarten. We’ve added more nieces and nephews to the family since then; I’ve seen graduations from college and high school; and my stepdaughter is expecting her first child. On top of all these blessings, I’m feeling great. I had forgotten how good I could feel."
