Lung cancer screening jargon

Here are some quick explanations for some of the words and phrases you've probably been reading about:

  • Risk: Risk means how likely you are to get lung cancer. You are at a higher risk of lung cancer if you have smoked or been exposed to things that are known to cause lung cancer, like asbestos. You start to be at high risk of lung cancer when you have smoked for 20 years. The more you smoke, the higher your risk is. Your risk of lung cancer also increases with age.
  • Pack-years: Pack-years are how we measure how much someone has smoked in their lifetime. It comes from a simple formula: Packs per day x Number of years smoked. For example, if you smoked 2 packs a day for 10 years, you would have smoked 20 pack-years. When you have more pack-years of smoking, you have a higher risk of lung cancer.
  • Screening: Screening is how we look for lung cancer. Our process uses repeated scans to look for changes that may be early lung cancer. The first time you are screened is called the baseline round of screening. The baseline CT scan may show us that you have a possible cancer at the very beginning of your screening process. The later rounds of screening are called repeat screenings and each new screening CT scan is compared to the ones you had in the past. Typically, lung cancer screening happens once per year.
  • Low-dose CT scan: The low-dose CT scan is used to give doctors a detailed view of your chest so that they can look for problems. A CT scan of the chest can be performed using low-dose or high-dose radiation; low-dose and high-dose refer to how much radiation is used. Screening should be done using low-dose because it is repeated each year. Learn more about the radiation levels here. CT scans of the chest done for reasons other than screening are usually high-dose scans, which give about more than 10 times the radiation dose of a low-dose CT scan.
  • Nodule: The word nodule refers to an abnormal unusual structure in the lungs that looks round or oval in shape. Most nodules result from prior infections, like pneumonia; these infections could happened even as early as in childhood. Other causes could be trauma (injury), or current infections or inflammation. These kinds of nodules are not cancer. Some of these, however, may look like cancer on a CT scans. To find out if the nodule is a cancer, another CT scan is usually performed 1-3 months later to see if the nodule is growing. The quality of the CT is important to determine growth as such growth is minimal and requires careful reading by the radiologist.
  • False positive: Some people call all nodules that are not cancer a “false positive”; we do not think this is the right way to describe them. Nodules seen on CT scans are real, but most are not lung cancer. Some nodules that are not lung cancer may still need to be treated because they are caused by other diseases. Thus, a nodule that is not cancer may still be important.
  • Regimen: A regimen is a set of guidelines for doing something. Screening is best done when following a well-defined regimen. The regimen provides the rules that doctors use to make decisions. In the case of lung cancer screening, these rules help doctors decide what to do about the findings on the low-dose CT scan, when to do another scan, when to do a biopsy.
  • Biopsy: A biopsy is a diagnostic test where a sample of cells is taken and examined under a microscope to see if any are abnormal. A CT scanner can be used so that the person performing the biopsy can insert a very thin needle into the nodule that is suspected to be cancer. The CT scan allows the person to confirm that the needle tip is in the right location. This kind of biopsy does not require surgery and is done as an outpatient procedure, meaning that people come in for the test and go home the same day.
  • Cure rate: The proportion of people among all those who have the disease but do not die of it. This is usually stated as a percentage, like 50%.

Are you wondering about a word or phrase not listed here? Send us an email and we'll do our best to give you an answer.