Some people will develop symptoms of lung cancer and visit their doctor. For many others, there are no symptoms until the disease is advanced. This is when the tumor grows in size or spreads to other parts of the body.

Cancer is difficult to treat at an advanced stage. Some doctors encourage lung cancer screening to help detect cancer sooner. Screening involves checking for lung cancer before symptoms become apparent.

But while screening can be extremely helpful, it also carries some risks. Here’s what you need to know about lung cancer screenings.

Because of the risks, screening for lung cancer isn’t recommended for everyone. The American Cancer Society’s guidelines suggest screening those with a higher risk for lung cancer. This includes heavy smokers between the ages of 55 and 74 years (heavy smoking means smoking a pack a day for 30 or more years).

Heavy smokers who’ve quit smoking in the past 15 years are also advised to get screened.

Those who get screened must be healthy enough to complete treatment if they’re diagnosed. Treatment might include chemotherapy, radiation, or surgery. Chemotherapy and radiation are designed to kill cancer cells, whereas surgery removes cancerous tumors.

Lung cancer is a serious illness. It’s the leading cancer killer in the United States, according to the Centers for Centers for Disease Control and Prevention (CDC). Like any cancer, the earlier you’re diagnosed, the better your prognosis.

Some people don’t have symptoms during early stages of the disease. Screening may detect small cancerous cells at their earliest stage. If you’re able to diagnose cancer when it hasn’t spread to other parts of the body, treatment may be more effective. It can help you achieve remission and improve the quality of life.

Although early screening for lung cancer has its benefits, there are also risks. Screening can result in false-positive results. A false positive is when results of a CT scan come back positive for cancer, yet the person doesn’t have the disease. A positive cancer reading requires further investigation to confirm the diagnosis.

After a positive CT scan, doctors perform a biopsy of the lungs. The sample is sent to a lab for testing. Sometimes a biopsy rules out malignant cells after a positive scan.

People who receive a false positive may undergo emotional turmoil or even surgery for no reason.

Early lung cancer screenings can also lead to an overdiagnosis of lung cancer. Even though a tumor is present in the lungs, it may never cause a problem. Or the cancer could be slow-growing and not cause problems for many years.

In both cases, treatment may be unnecessary at that time. Individuals must deal with grueling treatments, follow-up visits, higher medical expenses, and anxiety over a disease that may have otherwise gone undetected and not affected their quality of life.

Those who are overdiagnosed may also spend the rest of their lives getting tests to make sure cancer is no longer present. This can result in years of radiation exposure and increase their risk for other cancers.

Currently, there’s only one recommended screening test for lung cancer: low-dose computer tomography (low-dose CT scan). This test creates images of the inside of the body — or in this case, the lungs — using low doses of radiation.

Screening tests are conducted on those without symptoms. These tests look for abnormal lesions or tumors that could show early lung cancer. If a CT scan reveals an abnormality, additional testing is needed to confirm a lung cancer diagnosis. This includes a needle biopsy or surgery to remove sample tissue from your lungs.

Some candidates for lung cancer screening may choose to forgo screening. If you decide against screening, or if you’re not eligible, learn how to recognize early signs of lung cancer. That way, you can detect the cancer early and get treatment. Lung cancer symptoms include:

  • a progressive cough
  • coughing up blood
  • chest pains
  • hoarseness
  • loss of appetite
  • shortness of breath
  • fatigue
  • wheezing
  • respiratory infections

Screening for lung cancer has its benefits, but it may cause more harm than good. If you’re at risk for lung cancer and meet the screening guidelines, talk with your doctor to see if this is the right choice for you. Also, take steps to reduce your risk of lung cancer. This includes quitting smoking and avoiding secondhand smoke.