Lung cancer
Lung cancer is cancer that starts in the lungs.
The lungs are located in the chest. When you breathe, air goes through your nose, down your windpipe (trachea), and into the lungs, where it flows through tubes called bronchi. Most lung cancer begins in the cells that line these tubes.
There are two main types of lung cancer:
- Non-small cell lung cancer (NSCLC) is the most common type of lung cancer.
Non-small cell lung cancer
Non-small cell lung cancer is the most common type of lung cancer. It usually grows and spreads more slowly than small cell lung cancer. There are t...
Read Article Now Book Mark Article - Small cell lung cancer (SCLC) makes up about 20% of all lung cancer cases.
Small cell lung cancer
Small cell lung cancer (SCLC) is a fast-growing type of lung cancer. It spreads much more quickly than non-small cell lung cancer. There are two typ...
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If the lung cancer is made up of both types, it is called mixed small cell/large cell cancer.
If the cancer started somewhere else in the body and spreads to the lungs, it is called metastatic cancer to the lung.
Metastatic cancer to the lung
Lung metastases are cancerous tumors that start somewhere else in the body and spread to the lungs.
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Lung cancer - Animation
Cancer can affect just about any part of the body, from the colon to the pancreas. Some cancers grow quickly, while others grow more slowly and are easier to treat. But of all the different cancers out there, one of the deadliest is lung cancer. Let's talk today about lung cancer. Cancer starts when cells begin to grow uncontrollably and form tumors. In the case of lung cancer, the tumors start in the lungs. Sometimes cancer starts somewhere else in the body and then spreads to the lungs. In that case, it's called metastatic cancer to the lung. Metastatic means disease that has spread. There are two types of lung cancer. The most common, and slower-growing form is non-small cell lung cancer. The other, faster-growing form is called small cell lung cancer. The most common way to get lung cancer is to smoke cigarettes. The more cigarettes you smoke and the earlier you start smoking, the greater your risk is. Even being around someone who smokes and breathing in the secondhand smoke from their cigarettes increases your risk of getting lung cancer. Even though smoking makes you much more likely to get lung cancer, you don't have to smoke or be exposed to smoke to get the disease. Some people who have lung cancer never lit up a cigarette in their life. They have been exposed to cancer-causing substances like asbestos, diesel fumes, arsenic, radiation, or radon gas. Or, they may not have had any known lung cancer risks. The most common signs of lung cancer are a cough that won't go away, chest pain, shortness of breath, weight loss, and fatigue. But just because you have these symptoms it doesn't mean that you have don't have lung cancer. These can also be signs of other conditions, like asthma or a respiratory infection. If you do have these symptoms, see your doctor. A chest x-ray, MRI, or CT scan can view the inside of your lungs to look for signs of cancer or other diseases. What happens if you do have lung cancer? Doctors divide lung cancer into stages. The higher the stage, the more the cancer has spread. For example, a stage 1 cancer is small and hasn't spread outside of the lungs. A stage 4 cancer has spread to the other organs, such as the kidneys or brain. Depending upon the type and stage of your lung cancer, you may need surgery to remove part or all of your lung. Or, your doctor may recommend radiation or chemotherapy to kill cancer cells. If you have lung cancer, how well you do depends upon the stage of your disease and the type of lung cancer that you have. Early-stage cancers have the highest survival and cure rates. Late-stage cancers are harder to treat. Because lung cancer can be so deadly, prevention is key. The most important that thing you can do is to stop smoking, and avoid being around anyone who does smoke.
Causes
Lung cancer is the deadliest type of cancer for both men and women. Each year, more people die of lung cancer than of breast, colon, and prostate cancers combined.
Lung cancer is more common in older adults. It is rare in people under age 45.
Cigarette smoking is the leading cause of lung cancer. Close to 90% of lung cancer is related to smoking. The more cigarettes you smoke per day and the earlier you started smoking, the greater your risk for lung cancer. The risk does decrease with time after you stop smoking. There is no evidence that smoking low-tar cigarettes lowers the risk.
Certain types of lung cancer can also affect people who have never smoked.
Secondhand smoke (breathing the smoke of others) increases your risk for lung cancer.
The following may also increase your risk for lung cancer:
- Exposure to asbestos
- Exposure to cancer-causing chemicals such as uranium, beryllium, vinyl chloride, nickel chromates, coal products, mustard gas, chloromethyl ethers, gasoline, and diesel exhaust
- Exposure to radon gas
- Family history of lung cancer
- High levels of air pollution
- High levels of arsenic in drinking water
- Radiation therapy to the lungs
Symptoms
Early lung cancer may not cause any symptoms.
Symptoms depend on the type of cancer you have, but may include:
- Chest pain
Chest pain
Chest pain is discomfort or pain that you feel anywhere along the front of your body between your neck and upper abdomen.
Read Article Now Book Mark Article - Cough that does not go away
Cough
Coughing is an important way to keep your throat and airways clear. But too much coughing may mean you have a disease or disorder. Some coughs are d...
Read Article Now Book Mark Article - Coughing up blood
Coughing up blood
Coughing up blood is the spitting up of blood or bloody mucus from the lungs and throat (respiratory tract). Hemoptysis is the medical term for cough...
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- Losing weight without trying
Losing weight without trying
Unexplained weight loss is a decrease in body weight, when you did not try to lose the weight on your own. Many people gain and lose weight. Uninten...
Read Article Now Book Mark Article - Loss of appetite
Loss of appetite
A decreased appetite is when your desire to eat is reduced. The medical term for a loss of appetite is anorexia.
Read Article Now Book Mark Article - Shortness of breath
Shortness of breath
Breathing difficulty may involve:Difficult breathing Uncomfortable breathingFeeling like you are not getting enough air
Read Article Now Book Mark Article - Wheezing
Wheezing
Wheezing is a high-pitched whistling sound during breathing. It occurs when air moves through narrowed breathing tubes in the lungs.
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Other symptoms that may also occur with lung cancer, often in the late stages:
- Bone pain or tenderness
Bone pain or tenderness
Bone pain or tenderness is aching or other discomfort in one or more bones.
Read Article Now Book Mark Article - Eyelid drooping
Eyelid drooping
Ptosis (eyelid drooping) in infants and children is when the upper eyelid is lower than it should be. This may occur in one or both eyes. Eyelid dr...
Read Article Now Book Mark Article - Facial paralysis
Facial paralysis
Facial paralysis occurs when a person is no longer able to move some or all of the muscles on one or both sides of the face.
Read Article Now Book Mark Article - Hoarseness or changing voice
Hoarseness or changing voice
Hoarseness refers to a difficulty making sounds when trying to speak. Vocal sounds may be weak, breathy, scratchy, or husky, and the pitch or qualit...
Read Article Now Book Mark Article - Joint pain
- Nail problems
Nail problems
Nail abnormalities are problems with the color, shape, texture, or thickness of the fingernails or toenails.
Read Article Now Book Mark Article - Shoulder pain
- Swallowing difficulty
Swallowing difficulty
Difficulty with swallowing is the feeling that food or liquid is stuck in the throat or at any point before the food enters the stomach. This proble...
Read Article Now Book Mark Article - Swelling of the face or arms
Swelling of the face
Facial swelling is the buildup of fluid in the tissues of the face. Swelling may also affect the neck and upper arms.
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These symptoms can also be due to other, less serious conditions, so it is important to talk to your health care provider.
Exams and Tests
Lung cancer is often found when an x-ray or CT scan is done for another reason.
If lung cancer is suspected, the provider will perform a physical exam and ask about your medical history. You will be asked if you smoke. If so, you'll be asked how much you smoke and for how long you have smoked. You will also be asked about other things that may have put you at risk for lung cancer, such as exposure to certain chemicals.
When listening to the chest with a stethoscope, the provider may hear fluid around the lungs. This may suggest cancer.
Tests that may be done to diagnose lung cancer or see if it has spread include:
- Bone scan
Bone scan
A bone scan is an imaging test used to diagnose bone diseases and find out how severe they are.
Read Article Now Book Mark Article - Chest x-ray
Chest x-ray
A chest x-ray is an x-ray of the chest, lungs, heart, large arteries, ribs, and diaphragm.
Read Article Now Book Mark Article - Complete blood count (CBC)
- CT scan of the chest
- MRI of the chest
- Positron emission tomography (PET) scan
- Sputum test to look for cancer cells
- Thoracentesis (sampling of fluid buildup around the lung)
Thoracentesis
Thoracentesis is a procedure to remove fluid from the space between the lining of the outside of the lungs (pleura) and the wall of the chest....
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In most cases, a piece of tissue is removed from your lungs for examination under a microscope. This is called a biopsy. There are several ways to do this:
- Bronchoscopy combined with biopsy
Bronchoscopy
Bronchoscopy is a test to view the airways and diagnose lung disease. It may also be used during the treatment of some lung conditions.
Read Article Now Book Mark Article - CT-scan-directed needle biopsy
- Endoscopic esophageal ultrasound (EUS) with biopsy
- Mediastinoscopy with biopsy
Mediastinoscopy
Mediastinoscopy with biopsy is a procedure in which a lighted instrument (mediastinoscope) is inserted in the space in the chest between the lungs (m...
Read Article Now Book Mark Article - Open lung biopsy
Open lung biopsy
An open lung biopsy is surgery to remove a small piece of tissue from the lung. The sample is then examined for cancer, infection, or lung disease....
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Pleural biopsy
An open pleural biopsy is a procedure to remove and examine the tissue that lines the inside of the chest. This tissue is called the pleura....
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If the biopsy shows cancer, more imaging tests are done to find out the stage of the cancer. Stage means how big the tumor is and how far it has spread. Staging helps guide treatment and follow-up and gives you an idea of what to expect.
Treatment
Treatment for lung cancer depends on the type of cancer, how advanced it is, and how healthy you are:
- Surgery to remove the tumor may be done when it has not spread beyond nearby lymph nodes.
- Chemotherapy uses drugs to kill cancer cells and stop new cells from growing.
Chemotherapy
The term chemotherapy is used to describe cancer-killing drugs. Chemotherapy may be used to:Cure the cancer Shrink the cancerPrevent the cancer from...
Read Article Now Book Mark Article - Radiation therapy uses powerful x-rays or other forms of radiation to kill cancer cells.
Radiation therapy
Radiation therapy uses high-powered x-rays, particles, or radioactive seeds to kill cancer cells.
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The above treatments may be done alone or in combination. Your provider can tell you more about the specific treatment you will receive, depending on the specific type of lung cancer and what stage it is.
Support Groups
You can ease the stress of illness by joining a cancer support group. Sharing with others who have common experiences and problems can help you not feel alone.
Cancer support group
The following organizations are good resources for information on cancer:American Cancer Society -- www. cancer. orgAmerican Childhood Cancer Organiz...
Read Article Now Book Mark ArticleOutlook (Prognosis)
How well you do depends mostly on how much the lung cancer has spread.
When to Contact a Medical Professional
Call your provider if you have symptoms of lung cancer, particularly if you smoke.
Prevention
If you smoke, now is the time to quit. If you are having trouble quitting, talk with your provider. There are many methods to help you quit, from support groups to prescription medicines. Also, try to avoid secondhand smoke.
Support groups
It is hard to quit smoking if you are acting alone. Smokers usually have a much better chance of quitting with a support program. Stop smoking prog...
Read Article Now Book Mark ArticlePrescription medicines
Nicotine replacement therapy is a treatment to help people stop smoking. It uses products that supply low doses of nicotine. These products do not ...
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Mark Levin, MD, Hematologist and Oncologist, Farmington, CT. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team. Editorial update 09/28/2021.
Araujo LH, Horn L, Merritt RE, et al. Cancer of the lung: non-small cell lung cancer and small cell lung cancer. In: Niederhuber JE, Armitage JO, Kastan MB, Doroshow JH, Tepper JE, eds. Abeloff's Clinical Oncology. 6th ed. Philadelphia, PA: Elsevier; 2020:chap 69.
Gillaspie EA, Lewis J, Leora Horn L. Lung cancer. In: Kellerman RD, Rakel DP, eds. Conn's Current Therapy 2020. Philadelphia, PA: Elsevier 2020:862-871.
National Cancer Institute website. Non-small cell lung cancer treatment (PDQ) - health professional version. www.cancer.gov/types/lung/hp/non-small-cell-lung-treatment-pdq. Updated May 7, 2020. Accessed July 14, 2020.
National Cancer Institute website. Small cell lung cancer treatment (PDQ) - health professional version. www.cancer.gov/types/lung/hp/small-cell-lung-treatment-pdq. Updated March 24, 2020. Accessed July 14, 2020.
Silvestri GA, Pastis NJ, Tanner NT, Jett JR. Clinical aspects of lung cancer. In: Broaddus VC, Mason RJ, Ernst JD, et al, eds. Murray and Nadel's Textbook of Respiratory Medicine. 6th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 53.