Every year, over 150,000 people in the United States of America die of lung cancer, making lung cancer by far the leading cause of cancer death.[1] One reason why lung cancer is so deadly is that it often eludes detection until too late to save the patient. 80% of lung cancer patients are only diagnosed once their cancer has reached stage III or stage IV, by which point surgery is off the table.[2]
Although smoking is a huge risk factor for lung cancer, a 2018 American Society for Clinical Oncology (ASCO) study discovered that only 2% of current or former heavy smokers receive lung cancer screenings.
“Lung cancer screening rates are much lower than screening rates for breast and colorectal cancers, which is unfortunate,” says lead ASCO study author Danh Pham, MD, a medical oncologist. “It is unclear if the screening deficit is due to low provider referral or perhaps patient psychological barriers from fear of diagnosis. Lung cancer is unique in that there may be stigma associated with screening, as some smokers think that if cancer is detected, it would confirm they’ve made a bad lifestyle choice.”[3]
As a healthcare provider, there is a real opportunity to make a difference. In lung cancer, an ounce of prevention is worth a pound of cure: When lung cancer is detected early, patients are far more likely to survive.[4] Ask your patients about smoking habits—both past and present—and refer high-risk patients for screenings. You could be the difference between a diagnosis of stage II non-small cell lung cancer, with a 53% survival rate, and a diagnosis of stage IV non-small cell lung cancer, with a 10% survival rate.[5] Keeping a non-judgemental attitude reduces stigma, helping patients take care of their health. And of course, for smokers, encourage tobacco cessation to reduce their lifetime risk of lung cancer.
The U.S. Preventive Services Task Force recommends yearly lung cancer screening for people who[6]
● Have a history of heavy smoking, and
● Smoke now or have quit within the past 15 years, and
● Are between 55 and 80 years old.
Heavy smoking means thirty years of, on average, a pack of cigarettes a day. For example, a person could have this history by smoking one pack a day for 30 years or two packs a day for 15 years.
Traditional wisdom holds that there is often little benefit to early screenings for lung cancer.[7] Complicating the issue, there is no one accepted method of early screening. After all, one of the most commonly-used screening techniques, low-dose computerized tomography (LDCT)[8], exposes patients to radiation and can produce false positives.[9] Part of the issue is that it can take years for lung cancer to develop. And because the tumor is buried so deeply in the body, the patient cannot feel its presence. Breast cancer can make itself palpable — we all know the concept of feeling for lumps. But lung cancer is subtler.
However, new technologies offer exciting glimpses into the future of lung cancer screening. Liquid biopsies may soon offer new methods of early cancer detection and diagnosis.[10] Although pathologists may quibble with the term, as they are not true biopsies, liquid biopsies nonetheless offer a wealth of information about a patient’s cancer.
Liquid biopsy means testing a blood sample for DNA fragments shed by a tumor. With a liquid biopsy, healthcare providers can track a cancer’s growth and response to treatment in real time, while bypassing invasive tissue biopsies.[11] “We can already envision a day when “liquid biopsy” tests will be as common and useful as imaging techniques and “standard” biopsies, offering invaluable prognostic and predictive information,” writes Spanish oncologist Miguel Ángel Molina-Vila.[12]
The technology is not here yet, but the research is exciting and promising. Keep an eye on it—someday in the near future, you may be able to diagnose your patients earlier than ever before, with nothing but a simple blood sample.
Sources
[1] https://gis.cdc.gov/Cancer/USCS/DataViz.html
[2] https://thorax.bmj.com/content/60/4/268
[3] https://www.asco.org/about-asco/press-center/news-releases/vast-majority-heavy-smokers-not-screened-lung-cancer-despite
[4] https://lcfamerica.org/lung-cancer-info/survivor-spotlight-dr-michael-weitz/early-diagnosis-importance/
[5] https://www.cancer.org/cancer/non-small-cell-lung-cancer/detection-diagnosis-staging/survival-rates.html
[6] https://www.cdc.gov/cancer/lung/basic_info/screening.htm
[7] https://www.everydayhealth.com/lung-cancer/specialists/pros-and-cons-of-aggressive-screening-for-lung-cancer.aspx
[8] https://www.mayoclinic.org/tests-procedures/lung-cancer-screening/about/pac-20385024
[9] https://www.jwatch.org/fw112499/2017/01/31/lung-cancer-screening-real-world-has-high-false-positive
[10] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5099506/
[11] https://www.cancer.gov/publications/dictionaries/cancer-terms/def/liquid-biopsy
[12] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5099506/