Decoding lung cancer terminology can be tough—but we’re here to make it easier. In this blog, we’ll help you better understand nodules, also known as lesions, coin lesions, growths, or solitary pulmonary nodules. Nodules are abnormal (yet common) spots that may show up on your lung cancer screening scan or other imaging tests.

Why is it important to understand lung nodules? If you’re being screened for lung cancer or having other imaging tests done, it is possible that a lung nodule will be found, especially if you’re over 50. And while nodules can be cancerous, the vast majority (95%) of lung nodules are benign.

What are the features of a nodule?

  • Margin
    The margin is where the nodule is in contact with normal lung tissue. The margins of many cancers are uneven, look spiky, and are described as “speculated.” Most nodules that are not cancer have smooth or rounded margins or look like several rounded nodules together (also called “lobulated”).
  • Density
    Density describes how compact a substance like bone or tissue appears on an image. A nodule has a range of densities depending on what it is made of. Regardless of whether a nodule is cancer or not, it appears grey on a CT scan. Some nodules contain deposits of calcium, which makes them look white like bone. These calcified nodules are less likely to be cancer.
  • Size
    Most benign (not cancerous) nodules are small. If you have a nodule and you are at high risk for lung cancer, you may be asked to come back in a year or sooner for another screening imaging test just to make sure it hasn’t changed. Smaller nodules are usually followed by additional CT scans while larger nodules require further tests in addition to imaging scans, such as a biopsy.
  • Consistency
    When a nodule is solid, it is called a solid nodule. If it is hazy with no solid parts, it is called a non-solid nodule or a ground glass nodule (GGN) because it looks like ground glass. In some cases, a nodule may have a solid part of it with a hazy part around it. These are called part-solid or semi-solid nodules.

Your healthcare team will look at the nodule features to create a follow up plan. If nodules on your scan appear large, look suspicious, or have changed over time, your doctor may recommend additional imaging tests or a biopsy. Understanding lung nodules will help you ask the right questions and determine appropriate next steps with your doctor.

Click here to download our Understanding Nodules one-pager.

Want to learn more? Check out our library of free educational materials to help you every step of the way through your lung cancer journey.