Risks

Lung cancer screening carries several risks, such as:

• Being exposed to a low level of radiation. The amount of radiation you're exposed to during an LDCT is much less than that of a standard CT scan. It's equal to about half the radiation you're exposed to naturally from the environment in a year.
• Undergoing follow-up tests. If your scan shows a suspicious spot in one of your lungs, you may need to undergo additional scans, which expose you to more radiation, or invasive tests, such as a biopsy, which carry serious risks. If these additional tests show that you don't have lung cancer, you may have been exposed to serious risks that you would have avoided if you didn't undergo screening.
• Finding cancer that's too advanced to cure. Advanced lung cancers, such as those that have spread, may not respond well to treatment, so finding these cancers on a lung cancer screening test might not improve or extend your life.
• Finding cancer that may never hurt you. Some lung cancers grow slowly and may never cause symptoms or harm. It's difficult to know which cancers will never grow to hurt you and which ones must be removed quickly to avoid harm. If you're diagnosed with lung cancer, your doctor will likely recommend treatment. Treatment for cancers that would have remained small and confined the rest of your life may not help you and may be unnecessary.
• Missing cancers. It's possible that lung cancer may be obscured or missed on your lung cancer screening test. In these cases, your results may indicate that you don't have lung cancer when you actually do.
• Finding other health problems. People who smoke for a long time have an increased risk of other health problems, including lung and heart conditions that may be detected on a lung CT scan. If your doctor finds another health problem, you may undergo further testing and, possibly, invasive treatments that wouldn't have been pursued if you hadn't had lung cancer screening.