What is lung cancer?
Lung cancer starts when
abnormal cells grow out of control in the lung. They can invade nearby tissues
and form tumors. Lung cancer can start anywhere in the lungs and affect any
part of the
The cancer cells can
spread, or metastasize, to the
lymph nodes and other parts of the body.
Lung cancers are divided into small cell lung cancers (SCLC) and non-small cell lung cancers (NSCLC). Small cell lung cancers usually grow more quickly and are more likely to spread than non-small cell lung cancer.
cancer is the leading cause of cancer deaths in the world.footnote 1
What causes lung cancer?
Most lung cancer is
caused by smoking.
But sometimes lung cancer develops in people who have never smoked.
Being exposed to
secondhand smoke, arsenic, asbestos, radioactive dust, or
radon can increase your chances of getting lung
cancer. People who are exposed to radiation at work or elsewhere have a higher
chance of getting lung cancer.
What are the symptoms?
signs of lung cancer may include:
- Feeling short of breath.
- Chest pain.
- Having blood in any mucus that you cough up.
Because these symptoms are so general, many people don’t suspect lung cancer. And by the time they see a doctor, often the cancer has already started to spread.
If the cancer spreads within and beyond the chest, other symptoms may occur.
How is lung cancer diagnosed?
Your symptoms and your medical history-especially if you have any history of cancer in your family-will help your doctor decide how likely it is
that you have lung cancer and whether you need tests to be sure.
Lung cancer is usually first found on a chest
X-ray or a
CT scan. More tests are done to find out what kind of
cancer cells you have and whether they have spread beyond your lung. These
tests help your doctor and you find out what
stage the cancer is in. The stage is a rating to
measure how big the cancer is and how far it has spread.
How is it treated?
cancers are found in the early stages when treatment is most effective. When lung cancer is found before it has spread outside the lungs, about half of these people will live at least 5 more years.footnote 2 After lung cancer has spread outside the lungs, how long a person lives usually depends on how far the cancer has spread (the stage) by the time it is found.
Finding out that you have cancer can change your life. You may feel like your world has turned upside down and you have lost all control. Talking with family, friends, or a counselor can really help. Ask your doctor about support groups. Or call the American Cancer Society (1-800-227-2345) or visit its website at www.cancer.org.
Can you prevent lung cancer?
Lung cancer that is caused by smoking can be prevented.
So it is important to stop smoking-or to stop being around someone else’s
Even if you have smoked a long time, quitting can lower
your chances of getting cancer. If you already have lung cancer, quitting makes
your treatment work better and can help you live longer.
Frequently Asked Questions
Learning about lung cancer:
Living with lung cancer:
Health Tools help you make wise health decisions or take action to improve your health.
Decision Points focus on key medical care decisions that are important to many health problems.
Actionsets are designed to help people take an active role in managing a health condition.
More than 8 out of 10 lung
cancers are caused by smoking.footnote 3 Tobacco smoke contains carcinogens-substances that cause cancer. These substances damage lung cells, and over time the damaged cells can turn into lung cancer.
The more you smoke and the longer you have smoked, the higher your chances of getting lung cancer. You lower your chances when you quit or cut down on how much you smoke.
Cancer also may be caused by gene changes (mutations) that occur as you get older.
Symptoms of lung cancer may include:
- Coughing symptoms, such as:
- A new cough or a cough that doesn’t go away.
- In smokers who have a chronic cough, a change in how severe their cough is or how much they cough.
- Coughing up blood or bloody mucus.
- Chest symptoms, such as:
- Chest, shoulder, or back pain that doesn’t go away and often gets worse with deep breathing.
- New wheezing.
- Shortness of breath.
- General symptoms, such as:
- Swelling in the neck and face.
- Difficulty swallowing.
- Weight loss and loss of appetite.
- Increasing fatigue and weakness.
- Recurring respiratory infections, such as pneumonia.
When lung cancer spreads, there may be other
symptoms. For example, if it spreads to the spine or
bones, it may cause pain in the back or other bones or cause weakness in the arms or
legs. If it spreads to the brain, it may cause seizures, headaches, or vision
Lung cancer can start anywhere in the lungs and may affect any
part of the
respiratory system. This can cause breathing or heart problems, such as:
- Pleural effusion, which is the buildup of fluid
between the outer lining of the lungs and the chest wall. This is a common
condition with lung cancer.
- Coughing up large amounts of bloody sputum.
- Collapse of a lung (pneumothorax).
- Blockage of the airway (bronchial obstruction).
- Recurrent infections, such as
- Pericardial effusion, which is the buildup of fluid in
the space between the heart and the sac around the heart (pericardium). This
condition is not common with lung cancer.
As lung cancer grows, it may spread (metastasize) to other
parts of the body. Lung cancer is classified in
stages, which describe how far the cancer has grown and spread.
long-term outcome (prognosis) for lung cancer depends
on how much the cancer has grown and spread.
What Increases Your Risk
A risk factor for lung cancer is something that increases your chance of getting this cancer. Having one or more of these risk factors can make it more likely that you will get lung cancer. But it doesn’t mean that you will definitely get it. And many people who get lung cancer don’t have any of these risk factors.
About 85 out of 100 lung cancers are related to cigarette smoking.footnote 4 Smoking cigars or a pipe may also increase your risk for lung cancer.
Your risk of getting lung cancer increases:
- The longer you smoke.
- The more cigarettes you smoke each day.
Quitting smoking lowers your risk for getting cancer, and your risk keeps going down as
long as you don’t smoke. Even cutting down how much you smoke may reduce your
risk (but not as much as quitting completely).
If you live with a smoker, you have a higher risk for
lung cancer compared with a person who lives in a nonsmoking
For more information, see the topic Quitting Smoking.
Exposure to some substances may increase your risk for lung cancer, including:
- Marijuana. Smoking one marijuana cigarette, or a joint, may
affect the lungs as much as smoking a pack of cigarettes.footnote 5
- Certain chemicals. These include arsenic and asbestos.
- Radiation. This includes exposure from your work place, medical tests, or from the environment (such as radioactive dust).
- Radon gas. This includes exposure from your home or work place.
- Air pollution. Living where the air is very polluted can increase your risk for lung cancer.
Some gene changes (mutations) can increase the risk of getting lung cancer. These gene changes mostly occur as a person gets older.
When To Call a Doctor
Call 911 or other emergency services immediately if you:
- Have new or sudden onset of chest pain that is crushing or
squeezing, is increasing in intensity, or occurs with any other
symptoms of a heart attack, such as shortness of breath and nausea.
- Have new or sudden
- Are coughing up a lot of blood (not just streaks of blood or a
small amount of blood mixed with a lot of mucus) from your lungs.
- Have been vomiting and feel that you may pass out when you sit up
Call your doctor immediately if you have:
- Labored, shallow, rapid breathing with shortness of breath or
wheezing, even when you are resting.
- Swelling of your neck and face.
Call your doctor to find out when an evaluation is needed
- Have new chest pain (more than just discomfort when you cough)
that lasts a long time and gets worse when you breathe deeply.
- Develop symptoms of
pneumonia, such as shortness of breath, cough, and
- Have a cough that produces a small amount of bloody (bright red
or rust-colored) mucus.
- Frequently cough up yellow or green mucus from your lungs (not
postnasal drainage) for longer than 2 days.
- Vomit frequently from coughing.
- Have a cough that lasts longer than 4 weeks.
- Breathe normally when you are at rest but are very short of
breath after any physical exercise.
- Have increasing fatigue for no apparent reason.
- Have unexplained weight loss.
Who to see
Health professionals who can evaluate your symptoms
and your risk for lung cancer include:
- Family medicine doctor.
- General practitioner.
- Nurse practitioner.
- Physician assistant.
Health professionals who can evaluate and treat your lung
To prepare for your appointment, see the topic Making the Most of Your Appointment.
Exams and Tests
If your exam suggests that you may have lung cancer, your doctor may recommend other
tests, such as:
- CT scan.
- PET scan.
- Tissue sampling. Doctors can use a variety of tests to examine tissue or fluid samples under a microscope and look for cancer cells. Tests include:
Tests after diagnosis
After lung cancer has been diagnosed, testing
is done to find out whether the cancer has spread (metastasized) to other
organs in your body and to determine the
stage of the cancer.
- MRI of the brain, spine, or chest.
- CT scan of the brain, neck, chest, abdomen, or pelvis.
- PET scan.
- Bone scan.
- Endoscopic ultrasound (EUS). In this test, a small ultrasound probe at the end of the endoscope is placed
down the throat to the chest area. The ultrasound can help find cancer behind the breast bone or in lymph
nodes in the area. EUS may also be used to guide a biopsy of the lymph nodes, the lung, or other areas.
- Bone marrow aspiration and biopsy.
If you have non-small cell lung cancer, your doctor may check for tumor markers (biomarkers), such as PD-L1, EGFR, ALK, and KRAS, that are caused by gene changes (mutations) in cancer cells. This can help your doctor choose the treatment that will
work best for you.
Tests before surgery
A person whose lungs aren’t working well may not be a good
candidate for surgery. If surgery to remove cancer in all or part of a lung is being
considered, the following tests may be done:
Screening tests help your doctor look for a certain disease or condition before you have any symptoms. This can increase your chances of finding the problem early, when it’s more treatable.
Studies haven’t yet shown that routine screening for lung cancer saves lives or prevents lung cancer. But it may help people who have the highest risk for lung cancer-people 55 and older who are or were heavy smokers. Talk to your doctor about the pros and cons of lung cancer screening.
Treatment for both non-small cell lung
cancer (NSCLC) and small cell lung cancer (SCLC) may include the following:
- Surgery. This may involve removing the cancer,
the affected lobe of lung, or the entire lung.
- Radiation. Radiation is often used in combination with surgery or
chemotherapy or both. For more information, see Other Treatment.
- Chemotherapy. Chemotherapy can help control the growth and spread of the
cancer, but it is a cure in only a small number of people. For more information, see Medications.
- Laser therapy. Laser therapy uses a highly focused beam of light to kill cancer cells.
Other treatments for NSCLC include:
- Targeted therapy. Targeted therapy is the use of medicines such as tyrosine kinase inhibitors or monoclonal antibodies to block cancer growth.
- Photodynamic therapy (PDT). PDT uses medicine and a special light to treat cancer.
- Cryosurgery. Cryosurgery may be used to freeze and destroy lung tumors.
- Electrocautery. Electrocautery is the use of a low-voltage electrical charge to destroy tumors.
- Watchful waiting. Watchful waiting means being watched closely by your doctor but not having treatment until you show symptoms or a change of some kind. It is only used in rare cases.
Your doctor may check for tumor markers (biomarkers), such as EGFR, ALK, and KRAS, that are caused by gene changes (mutations) in cancer cells. This can help your doctor choose the treatment that will
work best for you.
Other treatments for SCLC include:
- Endoscopic stent placement. This is done to open a blocked airway so you can breathe more easily. A flexible lighted viewing instrument (endoscope) is used to place a small hollow tube (a stent) in your bronchial tubes if a tumor is making it hard for you to breathe.
Some treatments can cause side effects. Home treatment
measures may help.
Your quality of life is critical when you are considering your treatment choices.
Discuss your personal preferences with your
oncologist when he or she recommends treatment.
Additional information about lung cancer is provided by the National Cancer Institute at www.cancer.gov/cancertopics/types/lung.
Dealing with your emotions
If you have been recently diagnosed with lung cancer, you may feel
denial, anger, and grief. Reactions vary from person to person. Talk to your doctor about steps you can take to help with your
If you are having a hard time moving forward with your life, talk
with your doctor. Your cancer treatment center may offer counseling services.
You may also contact your local chapter of the American Cancer Society to help
you find a support group.
Having cancer can change your life in many ways. For support in managing these changes, see the topic
After initial treatment for
lung cancer, it is important to receive follow-up
oncologist will schedule regular checkups, usually
every 3 to 4 months, depending on the therapies used in initial treatment.
After 2 to 3 years, regular checkups will occur less often but more than just
once a year, depending on your medical history.
- Checkups may include a physical exam, blood tests,
chest X-rays, CT scans, or other laboratory tests
recommended by your oncologist.
You may be
interested in participating in research studies called
clinical trials. Clinical trials are based on the most
up-to-date information and are designed to find better ways to treat people who
People who do not want standard treatments or are not cured by
standard treatments may want to participate in clinical trials. These are
ongoing in most parts of the United States and in some other countries around
the world for all stages of lung cancer.
Palliative care is a kind of care for people who have a serious illness. It’s different from care to cure your illness. Its goal is to improve your quality of life-not just in your body but also in your mind and spirit.
You can have this care along with treatment to cure your illness.
Palliative care providers will work to help control pain or side effects. They may help you decide what treatment you want or don’t want. And they can help your loved ones understand how to support you.
One study of people with non-small cell lung cancer who started palliative care when they were diagnosed with lung cancer found that they not only felt better but also lived a little longer than the people who didn’t have palliative care.footnote 6
If you’re interested in palliative care, talk to your doctor.
For more information, see
For some people who have advanced cancer, a time comes when treatment to cure the cancer no longer seems like a good choice. This can be because the side effects, time, and costs of treatment are greater than the promise of cure or relief. But you can still get treatment to make you as comfortable as possible during the time you have left. You and your doctor can decide when you may be ready for hospice care.
Most lung cancers are caused by smoking. If
you use tobacco, you can help prevent lung cancer by quitting. For more information, see
Other prevention tips
You may be able to make other changes in your life that can help prevent lung cancer:
- Avoid working in jobs where you are exposed to asbestos, arsenic, or secondhand smoke.
- Check the radon level in your home. If your radon level is high, lowering it can reduce your risk.
- Don’t have unnecessary chest X-rays.
- Eat a healthy diet. Consider including a variety of foods, such as:
- Foods high in antioxidants, like beans, berries, prunes, and artichokes.
- Foods high in phytoestrogens, like soy foods (tofu, soy milk, and edamame), whole grains, sprouts (alfalfa and clover), seeds (flaxseed, sesame, sunflower, and pumpkin), and nuts.
- Cruciferous vegetables, like broccoli, cabbage, cauliflower, brussels sprouts, bok choy, kale, and collard greens.
Studies show that taking supplements of beta carotene or vitamin E does not affect the risk of lung cancer for non-smokers. But for smokers, especially those who smoke one or more packs a day, taking beta carotene supplements can actually increase their risk for lung cancer.footnote 7
During treatment for any stage of
lung cancer, there are steps you can take at home to manage some symptoms and side effects. Be sure to follow any instructions your doctor has given you.
- Home treatment for nausea or vomiting includes
watching for and treating early signs of
dehydration, such as a dry mouth, sticky saliva, and
reduced urine output.
- Home treatment for diarrhea includes resting your
stomach and being alert for signs of dehydration.
- Home treatment for constipation includes gentle
exercise along with adequate intake of fluids and a diet that is high in
fruits, vegetables, and fiber.
- Home treatment for fatigue includes making sure you
get extra rest while you are receiving
- Home treatment for pain includes heat and cold packs and learning how to distract yourself from the pain.
- Home treatment for a sore mouth includes avoiding certain foods and rinsing with mouthwash or an antacid.
- Home treatment for sleep problems includes having a
regular bedtime and avoiding caffeine late in the day.
Other issues you may be able to handle at home include:
- Loss of appetite or difficulty eating. Eating several small meals
throughout the day or eating soft, bland foods may help if you do not have an
appetite or if certain foods are difficult to eat.
- Coughing. You may have an ongoing cough or develop a severe
cough. Your doctor can recommend some nonprescription cough medicines or
prescribe some medicines to help relieve your symptoms.
If you smoke and have lung cancer, quitting smoking
will make your treatment more effective and may help you live longer. Smoking
delays healing after surgery, so you may have a better recovery from lung
cancer surgery if you have quit smoking.
People with early-stage lung cancer
who continue to smoke during radiation therapy have been shown to have shorter
survival times than those who do not smoke.footnote 8
also make chemotherapy less effective. The nicotine in tobacco seems to help
the cancer cells and their blood supply multiply while also protecting the
cancer cells from destruction.footnote 9
For information and
help quitting smoking, see the topic
Medicines for lung cancer mainly involve chemotherapy. Other medicines may be used to help with pain.
Chemotherapy is the most effective treatment for
small cell lung cancer. It can help control the growth and spread of the
cancer, but it cures lung cancer in only a small number of people. It
also may be used to treat more advanced stages of
non-small cell lung cancer.
Chemotherapy is called a systemic
treatment because the medicines enter your bloodstream, travel through your
body, and kill cancer cells both inside and outside the lung area. Some
chemotherapy drugs are taken by mouth (orally), while others are injected into
a vein (intravenous, or IV).
Some of the more common chemotherapy medicines used for lung cancer include the
You may be concerned about losing your hair
from cancer treatment. Not all chemotherapy medicines cause hair loss, and some
people have only mild thinning that is noticeable only to them. Talk to your
doctor about whether hair loss is an expected side effect of the medicines you
Chemotherapy may be combined with surgery. It may be given before or after surgery to kill cancer cells.
Medicines for pain
Pain is one of the main concerns of people who have cancer. But cancer pain can almost always be controlled with medicines and other options. Medicines used for cancer pain include prescribed medicines, such as hydrocodone or morphine, or nonprescription medicines, such as aspirin and similar drugs.
Lung surgery to remove
the cancer may be an option when your cancer is in only one lung or present in
one lung and in nearby lymph nodes. It usually is done only if your doctor
thinks all the cancer can be removed and your general health is good enough for
you to handle the surgery.
Nearby lymph nodes may also be removed to find out whether the cancer has
The type of surgery performed depends on the location and
size of your lung cancer:
- Wedge resection. The surgeon removes a small wedge-shaped piece of lung that contains the lung cancer and a margin of healthy tissue around the cancer.
- Lobectomy (say “low-BEK-tuh-mee”). The right lung has three lobes and the left lung has two lobes. A lobectomy removes the entire lobe of your lung that contains the cancer. Your lungs can function with the lobes that remain.
- Pneumonectomy (say “new-muh-NEK-tuh-mee”). A pneumonectomy removes your entire lung that contains the lung cancer.
- Sleeve resection. The surgeon removes part of the bronchus, the hollow tube at the end of the trachea (windpipe) that spreads into each lung like a tree.
The side effects from surgery will depend on the type of surgery that you have. There is less pain with surgery that is minimally invasive (VATS) than the traditional surgery (thoracotomy). You may have numbness and tingling in the chest area. This usually goes away in a few weeks or months.
Radiation treatment is the use of
high-energy X-rays to kill cancer cells and shrink tumors. Most radiation for lung cancer is given externally, which means that the radiation comes from a machine outside the body.
Radiation is often used in combination with
surgery or chemotherapy or both. But it may be used alone if surgery is not possible.
People who can’t have surgery may have a special type of radiation called stereotactic radiosurgery (SRS). This isn’t surgery but a series of very high doses of radiation that are aimed at the cancer. SRS is usually given to treat tumors that have spread to the brain. SRS may also be called gamma knife radiosurgery, cyberknife, stereotactic ablative radiotherapy (SABR), or stereotactic body radiotherapy (SBRT).
Radiation may be used to prevent small
lung cancer from growing in your brain. This is called
prophylactic cranial irradiation (PCI).
Radiation also may be used as
palliative care to:
- Shrink tumors that make it hard for you to swallow.
- Reduce tumors that block your airway and make it hard for you
- Relieve pain from cancer that has spread to your bones or
Radiation may cause
side effects, such as skin changes, fatigue, and trouble swallowing.
Other medical treatments
- Targeted therapy with monoclonal antibodies and tyrosine kinase inhibitors may be used to treat NSCLC. Monoclonal antibodies, such as bevacizumab, cetuximab, and nivolumab, can kill cancer cells, block their growth, and keep cancer from spreading. Tyrosine kinase inhibitors, such as erlotinib and gefitinib, can stop tumors from growing by blocking signals inside cancer cells.
- Laser therapy uses a narrow beam
of very intense light to destroy cancer cells. This treatment may be used to remove tumors that block the
- Photodynamic therapy
uses laser light to kill
cancer cells. It’s used as palliative treatment to destroy tumors that
block the airway.
- Electrocautery uses a probe or needle to burn (cauterize) abnormal tissue or tumors.
- Cryosurgery (also called
cryoablation) freezes the tumor and kills it.
- Radiofrequency ablation uses a small needle inserted through the skin and into the tumor. Energy passes
through the needle into the tumor. This heats and kills cancer cells. It also
closes up the little blood vessels in the area so there is less
- Stents-small, wire-mesh tubes-may be inserted into a blocked airway and expanded to hold the airway open.
- Watchful waiting means that you are being watched closely by your doctor but not having treatment until you show symptoms or a change of some kind.
People sometimes use complementary treatments along with medical treatment to help relieve symptoms and side effects of cancer treatments. Some of the complementary therapies that may be helpful include:
- Acupuncture to relieve pain.
- Meditation or yoga to relieve stress.
- Light massage (not deep tissue or intense pressure) or biofeedback to ease tension.
- Breathing exercises for relaxation.
These mind-body treatments may help you feel better. They can make it easier to cope with treatment. They also may reduce chronic low back pain, joint pain, headaches, and pain from treatments.
Before you try a complementary therapy, talk to your doctor about the possible value and potential side effects. Let your doctor know if you are already using any such therapies. They are not meant to take the place of standard medical treatment.
Other Places To Get Help
Atlanta, GA 30303
- Silverstri GA, Jett JR (2010). Clinical aspects of lung cancer. In R Mason et al., eds., Murray and Nadel’s Textbook of Respiratory Medicine, 5th ed., vol. 2, pp. 1116-1144. Philadelphia: Saunders.
- American Cancer Society (2012). Cancer Facts and Figures 2012. Atlanta: American Cancer Society. Available online: http://www.cancer.org/Research/CancerFactsFigures/CancerFactsFigures/cancer-facts-figures-2012.
- Khuri FR (2016). Lung cancer and other pulmonary neoplasms. In L Goldman, A Shafer, eds., Goldman-Cecil Medicine, 25th ed., vol. 2, pp. 1303-1313. Philadelphia: Saunders.
- U.S. Department of Health and Human Services (2010). A Report of the Surgeon General: How Tobacco Smoke Causes Disease-The Biology and Behavioral Basis for Smoking-Attributable Disease Fact Sheet. Available online: http://www.surgeongeneral.gov/library/tobaccosmoke/factsheet.html.
- Aldington S, et al. (2008). Cannabis use and risk of lung cancer: A case-control study. European Respiratory Journal, 31(2): 280-286.
- Temel JS, et al. (2010). Early palliative care for patients with metastatic non-small-cell lung cancer. New England Journal of Medicine, 363(8): 733-742.
- National Cancer Institute (2011). Small Cell Lung Cancer PDQ: Treatment-Patient Version. Available online: http://www.cancer.gov/cancertopics/pdq/treatment/small-cell-lung/Patient.
- Fox JL, et al. (2004). The effect of smoking status on survival following radiation therapy for non-small cell lung cancer. Lung Cancer, 44(3): 287-293.
- Dasgupta P, et al. (2006). Nicotine inhibits apoptosis induced by chemotherapeutic drugs by up-regulating XIAP and survivin. Proceedings of the National Academy of Sciences, 103(16): 6332-6337.
Other Works Consulted
- National Cancer Institute (2011). Small Cell Lung Cancer PDQ: Treatment-Patient Version. Available online: http://www.cancer.gov/cancertopics/pdq/treatment/small-cell-lung/Patient.
- National Cancer Institute (2012). Non-Small Cell Lung Cancer PDQ: Treatment-Patient Version. Available online: http://www.cancer.gov/cancertopics/pdq/treatment/non-small-cell-lung/Patient.
- National Cancer Institute (2012). Small Cell Lung Cancer PDQ: Treatment-Health Professional Version. Available online: http://www.cancer.gov/cancertopics/pdq/treatment/small-cell-lung/healthprofessional.
- Neville A (2009). Lung cancer, search date May 2008. Online version of BMJ Clinical Evidence: http://www.clinicalevidence.com.
Primary Medical Reviewer E. Gregory Thompson, MD – Internal Medicine
Kathleen Romito, MD – Family Medicine
Specialist Medical Reviewer Michael Seth Rabin, MD – Medical Oncology
Current as ofMay 3, 2017
Current as of:
May 3, 2017