Lung cancer is a type of cancer that begins in the lungs. Your lungs are two spongy organs in your chest that take in oxygen when you inhale and release carbon dioxide when you exhale.
Lung cancer is the leading cause of cancer deaths in the United States, among both men and women. Lung cancer claims more lives each year than do colon, prostate, ovarian and breast cancers combined.
People who smoke have the greatest risk of lung cancer. The risk of lung cancer increases with the length of time and number of cigarettes you've smoked. If you quit smoking, even after smoking for many years, you can significantly reduce your chances of developing lung cancer.
Tests and diagnosis
Testing healthy people for lung cancer
Several organizations recommend people with an increased risk of lung cancer consider annual computerized tomography (CT) scans to look for lung cancer. If you're 55 or older and smoke or used to smoke, talk with your doctor about the benefits and risks of lung cancer screening.
Some studies show lung cancer screening saves lives by finding cancer earlier, when it may be treated more successfully. But other studies find that lung cancer screening often reveals more benign conditions that may require invasive testing and expose people to unnecessary risks and worry.
Tests to diagnose lung cancer
If there's reason to think that you may have lung cancer, your doctor can order a number of tests to look for cancerous cells and to rule out other conditions. In order to diagnose lung cancer, your doctor may recommend:
- Imaging tests. An X-ray image of your lungs may reveal an abnormal mass or nodule. A CT scan can reveal small lesions in your lungs that might not be detected on an X-ray.
- Sputum cytology. If you have a cough and are producing sputum, looking at the sputum under the microscope can sometimes reveal the presence of lung cancer cells.
- Tissue sample (biopsy). A sample of abnormal cells may be removed in a procedure called a biopsy.
Your doctor can perform a biopsy in a number of ways, including bronchoscopy, in which your doctor examines abnormal areas of your lungs using a lighted tube that's passed down your throat and into your lungs; mediastinoscopy, in which an incision is made at the base of your neck and surgical tools are inserted behind your breastbone to take tissue samples from lymph nodes; and needle biopsy, in which your doctor uses X-ray or CT images to guide a needle through your chest wall and into the lung tissue to collect suspicious cells.
A biopsy sample may also be taken from lymph nodes or other areas where cancer has spread, such as your liver.
Lung cancer staging
Once your lung cancer has been diagnosed, your doctor will work to determine the extent (stage) of your cancer. Your cancer's stage helps you and your doctor decide what treatment is most appropriate.
Staging tests may include imaging procedures that allow your doctor to look for evidence that cancer has spread beyond your lungs. These tests include CT scans, magnetic resonance imaging (MRI), positron emission tomography (PET) and bone scans. Not every test is appropriate for every person, so talk with your doctor about which procedures are right for you.
Stages of lung cancer
- Stage I. Cancer is limited to the lung and hasn't spread to the lymph nodes. The tumor is generally smaller than 2 inches (5 centimeters) across.
- Stage II. The tumor at this stage may have grown larger than 2 inches, or it may be a smaller tumor that involves nearby structures, such as the chest wall, the diaphragm or the lining around the lungs (pleura). Cancer may also have spread to the nearby lymph nodes.
- Stage III. The tumor at this stage may have grown very large and invaded other organs near the lungs. Or this stage may indicate a smaller tumor accompanied by cancer cells in lymph nodes farther away from the lungs.
- Stage IV. Cancer has spread beyond the affected lung to the other lung or to distant areas of the body.
Small cell lung cancer is sometimes described as being limited or extensive. Limited indicates cancer is limited to one lung. Extensive indicates cancer has spread beyond the one lung.
Treatments and drugs
You and your doctor choose a cancer treatment plan based on a number of factors, such as your overall health, the type and stage of your cancer, and your preferences. Options typically include one or more treatments, including surgery, chemotherapy, radiation therapy or targeted drug therapy.
In some cases you may choose not to undergo treatment. For instance, you may feel that the side effects of treatment will outweigh the potential benefits. When that's the case, your doctor may suggest comfort care to treat only the symptoms the cancer is causing, such as pain or shortness of breath.
During surgery your surgeon works to remove the lung cancer and a margin of healthy tissue. Procedures to remove lung cancer include:
- Wedge resection to remove a small section of lung that contains the tumor along with a margin of healthy tissue
- Segmental resection to remove a larger portion of lung, but not an entire lobe
- Lobectomy to remove the entire lobe of one lung
- Pneumonectomy to remove an entire lung
If you undergo surgery, your surgeon may also remove lymph nodes from your chest in order to check them for signs of cancer.
Lung cancer surgery carries risks, including bleeding and infection. Expect to feel short of breath after lung surgery. If a portion of your lung is removed, your remaining lung tissue will expand over time and make it easier to breathe. Your doctor may recommend a respiratory therapist who can guide you through breathing exercises to aid in your recovery.
Chemotherapy uses drugs to kill cancer cells. One or more chemotherapy drugs may be given through a vein in your arm (intravenously) or taken orally. A combination of drugs usually is given in a series of treatments over a period of weeks or months, with breaks in between so that you can recover.
Chemotherapy is often used after surgery to kill any cancer cells that may remain. It may also be used before surgery to shrink cancers and make them easier to remove. In some cases, chemotherapy can be used to relieve pain and other symptoms of advanced cancer.
Radiation therapy uses high-powered energy beams from sources such as X-rays and protons to kill cancer cells. Radiation therapy can be directed at your lung cancer from outside your body (external beam radiation) or it can be put inside needles, seeds or catheters and placed inside your body near the cancer (brachytherapy).
Radiation therapy can be used after surgery to kill any cancer cells that may remain. It may also be used as the first treatment for lung cancers that can't be removed during surgery. For people with advanced lung cancer, radiation therapy may be used to relieve pain and other symptoms.
For people with lung cancers that are very small, one option may be stereotactic body radiotherapy. This form of radiation aims many beams of radiation from different angles at the lung cancer. Stereotactic body radiotherapy treatment is typically completed in one or a few treatments. In certain cases, it may be used in place of surgery for small tumors.
Targeted drug therapy
Targeted therapies are newer cancer treatments that work by targeting specific abnormalities in cancer cells. Targeted therapy drugs are often used in combination with chemotherapy drugs.
Targeted therapy options for treating lung cancer include:
- Afatinib (Gilotrif)
- Bevacizumab (Avastin)
- Ceritinib (Zykadia)
- Crizotinib (Xalkori)
- Erlotinib (Tarceva)
- Nivolumab (Opdivo)
- Ramucirumab (Cyramza)
Some targeted therapies only work in people whose cancer cells have certain genetic mutations. Your cancer cells will be tested in a laboratory to see if these drugs might help you.
Clinical trials are studies of experimental lung cancer treatments. You may be interested in enrolling in a clinical trial if lung cancer treatments aren't working or if your treatment options are limited.
The treatments studied in a clinical trial may be the latest innovations, but they don't guarantee a cure. Carefully weigh your treatment options with your doctor.
Your participation in a clinical trial may help doctors better understand how to treat lung cancer in the future.
People with lung cancer often experience signs and symptoms of the cancer, as well as side effects of treatment. Supportive care, also known as palliative care, is a specialty area of medicine that involves working with a doctor to minimize your signs and symptoms.
Your doctor may recommend that you meet with a palliative care team soon after your diagnosis to ensure that you're comfortable during and after your cancer treatment.
In one study, people with advanced non-small cell lung cancer who began receiving supportive care soon after their diagnosis lived longer than those who continued with treatments, such as chemotherapy and radiation. Those receiving supportive care reported improved mood and quality of life. They survived, on average, almost three months longer than did those receiving standard care.
You may be concerned that receiving palliative care means you can't undergo aggressive treatment for your cancer. But rather than replace curative treatments, palliative care complements your cancer treatment and may make it more likely that you can complete your treatments.