Lung cancer is the deadliest form of cancer in the United States, responsible for approximately 160,000 deaths annually. This toll is higher than the combined deaths from the next three most common cancers—colon, breast, and prostate. Yet, despite the severity, only about 30% of lung cancer cases are diagnosed at an early stage when treatment is most effective. Most patients learn of their condition only at a later, less treatable stage, which significantly lowers their chances of survival.
Evidence-based screening for high-risk individuals is one of the best hopes to catch the disease early and provide a chance for effective treatment. Given that about 20% of lung cancer deaths are preventable, increasing awareness and adherence to screening guidelines is critical for reducing the burden of this disease.
The Importance of Screening
Lung cancer screening is a vital tool for public health and has made it a priority to promote evidence-based screening practices. It is recommended that lung cancer screening with low-dose computerized tomography (CT) scans be considered standard care for high-risk patients and that such screenings be covered by Medicare, Medicaid, and private insurance as a mandatory benefit.
The policy also aims to raise awareness of lung cancer screening in high-risk patients to improve screening rates and reduce the number of deaths from this leading cause of cancer in the U.S. As part of its initiative, the AMA’s “What Doctors Wish Patients Knew™” series provides a platform for physicians to share important health information directly with patients. In this installment, Dr. Omar Atiq, a medical oncologist and former president of the American College of Physicians, discusses what patients need to know about lung cancer screening and prevention.
Smoking: The Leading Risk Factor
Smoking is the primary risk factor for lung cancer, accounting for the majority of preventable cancer deaths. Dr. Atiq explains, “In general, anybody can have any cancer based on a number of different factors, but the factor that causes the most preventable cancer deaths is smoking.” This includes cigarette, pipe, and cigar smoking, with cigarette smoking being the most prevalent in the United States.
Other risk factors include exposure to heavy metals like arsenic, lead, and uranium, as well as environmental factors such as air pollution. However, these factors are not as clearly defined or as directly linked to lung cancer risk as smoking. “We don’t know yet whether vaping, e-cigarettes, or even cannabis are related to an increased risk of lung cancer,” Dr. Atiq notes. “We believe it may be, especially for cannabis, but the data is not as robust as it is for tobacco.”
Annual Screenings for High-Risk Patients
For individuals at high risk due to their smoking history, yearly screenings are strongly recommended. The U.S. Preventive Services Task Force (USPSTF) advises that anyone between the ages of 50 and 80 with a 20-pack year history of cigarette smoking should undergo annual low-dose CT scans. But what exactly is a 20-pack year history? It’s a measure that combines the number of packs smoked per day with the number of years a person has smoked. For example, smoking two packs a day for 10 years or one pack a day for 20 years both equate to a 20-pack year history.
Screening is recommended for those who currently smoke or have quit within the last 15 years and who are otherwise healthy enough to tolerate potential treatments if lung cancer is detected. Those who quit smoking over 15 years ago generally have a lower risk, but this does not mean their risk is nonexistent.
Interestingly, the American Cancer Society’s updated guidelines no longer consider the time since quitting smoking as a barrier to screening. They recommend annual screenings for all individuals aged 50 to 80 who have a 20-pack year history, regardless of how long ago they quit smoking.
The Role of Low-Dose CT Scans in Lung Cancer Detection
Low-dose CT scans are the preferred method for lung cancer screening in high-risk individuals. These scans use lower amounts of radiation compared to standard diagnostic CT scans but still provide a detailed image that can help detect early-stage lung cancer. “Low-dose CT scans are sophisticated CT scanners where you do not get the full dose of radiation that you get on a diagnostic CT scan,” explains Dr. Atiq. “But you do get a good enough picture for the radiologist to be able to find a small lung cancer if there is one.”
Older CT technologies are not sufficient for this purpose, emphasizing the need for up-to-date equipment and protocols in screening programs.
Conclusion
Lung cancer remains a significant public health challenge, claiming more lives each year than any other cancer. Early detection through regular screenings offers the best chance of reducing these deaths. The evidence is clear: high-risk individuals, particularly those with a history of smoking, should undergo annual low-dose CT scans to catch lung cancer early when it is most treatable. As awareness and adherence to screening guidelines improve, the hope is to decrease lung cancer’s devastating impact on individuals, families, and communities across the country.
Source: American Medical Association