Trusted medical advice from the
American Academy of Family Physicians.

Lung Cancer

What is lung cancer?

Lung cancer is abnormal growth of cells in the lungs. It is one of the most common forms of cancer in the world. More people in the United States die from lung cancer than any other cancer. Most cases of lung cancer are caused by smoking.

There are 2 types of lung cancer:
Non-small cell – This is the most common form of lung cancer. More than 85% of people with lung cancer have non-small cell.
Small cell – The cells of this form of cancer are small. The cells grow and spread faster than in non-small cell lung cancer. It is treated differently.

Symptoms of lung cancer

Symptoms of lung cancer can differ from person to person. Common symptoms include:

  • A cough that gets worse or won’t go away
  • Chest pain
  • Shortness of breath or wheezing
  • Ongoing problems with pneumoniaor bronchitis
  • Coughing up blood
  • Feeling tired all the time
  • Unexplained weight loss

Some people report just not feeling well. If the cancer has spread, you might feel pain or have problems with the part of the body it has spread to. Many people with lung cancer don’t experience symptoms until the disease is in an advanced stage. That is one of the reasons more people die from it.

What causes lung cancer?

There are several known causes of lung cancer.

In most cases (80% to 90%), smoking causes lung cancer. Cigarette smoke contains thousands of chemicals. Many of these are known to cause cancer. Smokers are 15 to 30 times more likely to develop lung cancer than non-smokers. People who use other tobacco products are also at increased risk of getting lung cancer. These products include cigars, pipes, and electronic cigarettes (e-cigarettes or vape).

Your risk of getting lung cancer is higher the earlier you started smoking, and the more cigarettes you smoked per day. If you used to smoke but don’t anymore, your risk of lung cancer decreases. But it is still higher than if you never smoked at all.

Secondhand smoke

Secondhand smoke is the smoke that other people make when they are smoking tobacco products. When you breathe it in, you are still getting the harmful effects from the smoke. Thousands of people who never smoked die every year from lung cancer because they’ve been around secondhand smoke.

Radon is a gas that occurs naturally in the earth. It gets trapped in houses and buildings. There, it can reach high levels that can cause cancer. Exposure to radon is the second-leading cause of lung cancer in the U.S.

Other substances
A variety of other substances have been linked to lung cancer. These include asbestos, arsenic, diesel exhaust, and certain forms of silica and chromium.

How is lung cancer diagnosed?

Lung cancer is often found on an X-ray or CT scan being done for another reason. If you have symptoms of lung cancer, your doctor will do a physical exam. He or she will listen to your chest. If they hear fluid around your lungs, they may suspect lung cancer. They will ask you about your medical history, and if you smoke. They will also ask if you’ve been exposed to other things that can cause cancer, such as asbestos.

Your doctor will probably order tests that can look for lung cancer. Some of these tests may include:

  • chest X-ray
  • CT scan
  • MRI
  • PET (positron emission tomography) scan
  • Sputum test
  • Thoracentesis (samples fluid that has built up around the lungs)

If any of these tests indicate cancer may be present, your doctor will probably order a biopsy. They will remove a piece of tissue from your lung. They will look at the tissue under a microscope and look for cancer cells.

If cancer cells are found in a biopsy, your doctor will do more testing. This will help them find out how quickly the cancer may grow, how likely it will or has spread, and how certain treatments might work.

Can lung cancer be prevented or avoided?

In most cases, lung cancer can be prevented.

  • Don’t smoke. If you don’t smoke, don’t start. If you do smoke, try to quit. If you vape, quit. If you need help quitting, talk to your doctor. There are many methods available to help you. These include the nicotine patch, gum, and medicine.
  • Avoid secondhand smoke. If you spend time with people who smoke, ask them to not smoke around you. Avoid places where there will be secondhand smoke.
  • Have your home tested for radon. This is recommended by the Environmental Protection Agency. If your homes tests for high levels of radon gas, you can install a radon mitigation system to vent the gas outside of your home.
  • Avoid carcinogens. Carcinogens are things that cause cancer. Other common carcinogens (in addition to smoke, radon, and asbestos) that can cause lung cancer include diesel exhaust, coal dust, and other types of soot.

If you smoke and are between 55 and 80 years old, you can get a screening for lung cancer. This is done through a low-dose CT scan. Screening helps find cancer earlier or before it spreads. This improves your chances of successful treatment.

Lung cancer treatment

There are several treatment options for lung cancer. Your doctor may recommend more than one type of treatment. What is best for one person may not be the best treatment for you. Your doctor will make the decision based on several things, including:

  • Your general health
  • The type of lung cancer
  • Where the cancer has spread

Common available treatments include:

  • Surgery – A surgeon cuts out the tumor or any cancerous tissue.
  • Radiation therapy – High-energy rays are used to kill cancer cells. It may be used after surgery to destroy any cancer cells that are still there.
  • Chemotherapy – Powerful medicines are used to kill cancer cells. They are given through an IV (directly into the vein) or in pill form. Chemotherapy can cause unpleasant side effects. These include weakness, fatique, and hair loss.
  • Targeted therapy – Special medicines block the growth and spread of specific cancer cells. They can be given in an IV or as a pill.

People with non-small cell lung cancer can be treated with any of these therapies, or a combination. People with small cell lung cancer are usually treated with radiation and chemotherapy. Other therapies are also available. Ask your doctor which is the right treatment for you.

Living with lung cancer

With treatment, your lung cancer can go into remission. How well you do after treatment depends on many things. This includes how early the cancer was diagnosed. Left untreated or undetected, lung cancer can spread to other parts of the body. This includes lymph nodes and other organs. For many people, their cancer isn’t diagnosed until it has already spread. This could cause serious health problems or be fatal. It is very important to get treatment as soon as possible.

Living with cancer during treatment can be stressful. Treatments can have different side effects on your body. Take good care of yourself. Eat a healthy diet, get plenty of sleep, and try to keep your energy up by staying mildly active. Living with lung cancer also can affect your emotions. Get support where you need it. Family, friends, counselors, or support groups can all help you emotionally.

Even after your cancer is gone, you are at higher risk of cancer returning to your body. You will need to get regular follow-up care and check-ups for years after your treatment.

Questions to ask your doctor

  • What type of lung cancer do I have?
  • What are my treatment options?
  • What can I do to prepare for treatment?
  • Will there be any side effects?
  • How can I manage the side effects?
  • Will I be able to work while I’m receiving treatment?
  • Should I look into joining a clinical trial for treatment?
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