Curriculum · Screening (National/International)
Lung cancer screening
What it is
Lung cancer screening is done with low-dose computed tomography, written LDCT, and not with a chest X-ray. It is done annually in the people it covers.
Causes and risk
Smoking history is what places an adult in the screened group: a heavy pack-year history in an adult who still smokes or who stopped within the past 15 years. Adults with no smoking history are not screened, and having quit more than 15 years ago takes an adult out of the group. The reason behind screening is the death rate. From 2011 to 2015 the leading causes of cancer death in men were lung cancer at 53.8 deaths per 100,000 per year, prostate cancer at 19.5 deaths per 100,000 per year, colorectal cancer at 17.3 deaths per 100,000 per year, and pancreatic cancer at 12.6 deaths per 100,000 per year.
How it presents
Screening is for people with no symptoms, but one sign points at the lung by itself. Hypertrophic osteoarthropathy (HOA) is a condition where digital clubbing is accompanied by sudden-onset arthropathy, commonly affecting the wrist and hand joints. Hypertrophic pulmonary osteoarthropathy (HPOA) is a subset of HOA where the clubbing and arthropathy are attributable to underlying lung disease like lung cancer, tuberculosis, bronchiectasis, or emphysema. The development of clubbing and sudden-onset joint arthropathy in a chronic smoker is suggestive of hypertrophic osteoarthropathy, and because that is often associated with lung cancer a chest x-ray is indicated to rule out malignancy and other lung pathology. So the chest x-ray, which is not the screening test, is the appropriate initial study once that sign appears.