The majority of lung cancers are diagnosed in the later stages of the condition. Screening can help detect lung cancer earlier in high risk groups. This can lead to earlier treatment, which improves outlook.

Most cases of lung cancer aren’t detected early. Just 16% of lung cancers are found in the early stages, according to the American Lung Association (ALA).

Early detection of lung cancer with low dose CT (LDCT) scans can decrease the rate of lung cancer mortality by 14% to 20% for high risk groups, the ALA suggests. Screening helps find cancer early, when it is easiest to treat.

Roughly 8 million people in America meet the criteria for annual lung cancer screening, the ALA notes. If just half of these people were screened, more than 12,000 lung cancer deaths could be prevented.

When lung cancer is caught early, before it spreads to other parts of the body, the likelihood of survival for 5 or more years goes up to 60%.

Learn more about lung cancer screening, who should get screened, what kind of testing is involved, and the next steps if cancer is detected.

In many cases, lung cancer does not cause symptoms in the early stages. This is why most cases of lung cancer are diagnosed in late stages. A late diagnosis reduces the overall rate of survival and makes treatment more difficult.

Plus, symptoms of lung cancer may be mistaken for other health concerns. These symptoms include:

  • persistent cough
  • coughing up spit that is the color of rust
  • chest pain
  • unexplained weight loss
  • hoarseness
  • pain in the bones
  • shortness of breath

The majority of lung cancers are found when a person has symptoms in the later stages of cancer. Screening can help find lung cancer before symptoms even appear.

An LDCT scan is a screening tool used to check for lung cancer in people who don’t have symptoms but may be at higher risk of developing the condition.

Screening refers to testing for a health condition even if a person has no symptoms. People who are at increased risk of lung cancer should receive screening.

Lung cancer screening reduces the risk of dying from lung cancer and increases the chance of finding the condition early when treatment is most effective. This also improves outlook.

The U.S. Preventive Services Task Force uses available evidence to make recommendations for screening and preventive treatment. The organization recommends yearly lung cancer screening for people who meet all three of the following criteria:

  • are between 50 and 80 years old
  • have a 20-pack-year or more smoking history
  • Smoke currently or have quit smoking in the last 15 years

“Pack-year” is a term used to calculate how much a person smokes in their lifetime. A 1-pack-year would be the equivalent of smoking 20 cigarettes (1 pack) on average each day for a year.

A person can have a 20-pack-year smoking history either by smoking 1 pack of cigarettes per day for 20 years or smoking 2 packs of cigarettes per day for 10 years.

Screening involves an LDCT scan. Screening for people who meet the criteria should occur every year until one of the following occurs:

  • The person hasn’t smoked for 15 years.
  • The person has a health issue that would limit life expectancy or their ability to have lung surgery.

While there are a number of potential risk factors for lung cancer, screening is recommended only for those who meet the smoking history criteria.

The American Lung Association has a quiz that can help determine whether you should be screened for lung cancer.

An LDCT scan is the only recommended screening test for lung cancer.

If you are deemed an appropriate candidate for screening, ask your doctor about the benefits and risks of screening.

The benefit of lung cancer screening is that the test can find 80% of lung cancers when they are at an earlier stage and easier to treat, according to the ALA. If screening doesn’t occur, 70% of lung cancers will instead be found at a later stage when it is harder to treat.

Lung cancer screening does carry some risks. These include:

  • low exposure to radiation
  • false positives
  • overdiagnosis

The majority of health insurance companies will cover the cost of lung cancer screening for people who meet the criteria.

What happens in a low dose CT scan?

Prior to screening, you will be asked to remove any metal like jewelry and watches. You may be able to stay in your clothes, or you may be asked to change into a hospital gown.

The scan should not be performed if you have certain underlying conditions. People who receive screening need to be in good enough health that they can undergo surgery or other treatments to treat lung cancer if necessary.

The scan itself is painless and quick. It typically takes less than a minute.

You will be asked to lie down on a table that will slide in and out of the scanning machine. The machine is shaped like a large doughnut. It is important to lie still during this process. You may also be asked to hold your breath.

The scan technologists will give you instructions throughout the screening. Following the test, your doctor will contact you to discuss the results of the scan.

If a screening test shows something atypical, either in the lungs or in areas nearby, further investigation may be required.

In many cases, atypical findings end up not being cancer. But follow-up scans and tests are needed to be sure.

If a small nodule is found during a screening, you may have to get a follow-up CT scan to see if the nodule grows. If a nodule is found that seems suspicious, your doctor may recommend a PET scan or biopsy.

If these tests confirm lung cancer, discuss treatment options with your doctor. These may include:

  • chemotherapy
  • surgery
  • radiation
  • immunotherapy
  • targeted therapies

Lung cancer often doesn’t cause symptoms in the early stages, so the majority of people receive a diagnosis when lung cancer has progressed.

Lung cancer screening can help find lung cancer before symptoms develop. Finding lung cancer earlier improves survival rates because lung cancer is easier to treat in the early stages.

Some people with a history of smoking are advised to be screened annually for lung cancer. Ask your doctor whether you should be screened for lung cancer.