The glossary explains some of the words used across this website and covers some key cancer and research terms, which primarily focus on lung cancer.

Late presentation

A scenario where an individual seeks medical care after they have been experiencing common symptoms of lung cancer for some time. For example, they may not recognise the common symptoms of lung cancer (such as breathlessness, a cough or weight loss) and may delay making a medical appointment, meaning the disease continues to progress undetected.1 See also ‘Advanced lung cancer’ and ‘Early detection’


An area of damage or abnormality in tissue, which can be caused by an injury or a disease such as lung cancer.2

Liquid biopsy

A blood test that detects signs of cancerous tumours. It does this by detecting trace amounts of cancer cells or cancer-cell DNA.3 See also ‘molecular diagnostic testing’

Low-dose computed tomography (LDCT)

A non-invasive medical imaging technology, where a computer is linked to an X-ray machine to build a series of detailed images from different angles (slices), which are used to build a 3D profile of inside the body (scan).4 LDCT emits a very low amount of radiation and is recommended for individuals at high risk of lung cancer, as it is more sensitive than other imaging techniques such as chest X-ray. See also ‘Chest X-ray’ and ‘Computed tomography’

Lung cancer

When cancer first forms in the tissue of the lung, it is called lung cancer. There are two main types of lung cancer, classified by which type of cell is first affected: small-cell lung cancer and non-small-cell lung cancer.2 See also ‘Non-small-cell lung cancer’, ‘Small-cell lung cancer’ and ‘Symptoms’


  1. Weller DP, Peake MD, Field JK. 2019. Presentation of lung cancer in primary care. Primary Care Respiratory Medicine 29(1): 21

  2. National Cancer Institute. NCI Dictionary of Cancer Terms.  Available from: [Accessed 04/03/22]

  3. Cleveland Clinic. 2022. Liquid Biopsy. Available from: [Accessed 10/08/2023]

  4. Bonney A, Malouf R, Marchal C, et al. 2021. Low‐dose computed tomography (LDCT) screening for lung cancer‐related mortality. Cochrane Database of Systematic Reviews: 10.1002/14651858.CD013829 (1):