7 common myths about lung cancer

Lung cancer kills more Americans than any other type of cancer, claiming more lives than prostate cancer and colon cancer combined, and nearly three times as many deaths as breast cancer. Although pink ribbons have become a common sight for breast cancer awareness, and 4 out of every 5 women undergo mammography examinations at the recommended times, the demand for early detection of lung cancer is still much lower.

This disease is often viewed as primarily affecting heavy smokers, but the reality is more complex than that. Modern technologies provide new opportunities to detect lung cancer in its early stages, so it is easier to treat.

But official screening guidelines, which play a key role in determining whether insurance will cover its cost, often fail to accurately identify people at risk. What's more, only 20% of people eligible for testing actually get it.

This failure is due to the continued spread of misconceptions about lung cancer. Myth 1: Lung cancer only affects smokers About a quarter of lung cancer cases occur in people who have never smoked, defined as those who have smoked fewer than 100 cigarettes in their lifetime.

Lung cancer in non-smokers is more common among women than men, especially women of East Asian or South Asian descent. One study found that 83% of women with lung cancer in South Asia had never smoked.

Myth 2: Only smokers are at risk The INSPIRE study, launched by Dr. Chi-Fu Jeffrey Yang, a thoracic surgeon at MassGeneral Brigham Cancer Institute, in collaboration with medical students Alex Potter and Deepti Srinivasan, is investigating the possibility of lung cancer screening for black patients who have ever smoked, even if they do not meet the criterion of smoking a pack of cigarettes a day for 20 years. These patients face a greater risk, as they are less likely to undergo early detection tests for lung cancer, although they are more likely to die from the disease.

This is partly due to their tendency to smoke only sparingly or intermittently, meaning they do not smoke “enough” to meet the screening requirements. During the first phase of the INSPIRE study, several cases of lung cancer were detected in participants who did not meet current eligibility criteria for screening.

In general, it has been found that more than half of lung cancer cases are diagnosed in people who do not meet the requirements for early detection examinations. The disease is not discovered in these people until symptoms appear, or incidentally while undergoing a CT scan for another reason, such as a rib injury or a heart examination.

Yang said the risk of lung cancer is affected by environmental factors, such as air pollution and radon gas, and by genetic factors, as well as smoking. But he believes that the standard of smoking for 20 years with a pack of cigarettes a day excludes many people who are most at risk, adding: “I think that the number of years a person has smoked is more important than the intensity of smoking.”

Myth 3: All screening guidelines are based on the latest research CT lung cancer screening is done with low-dose radiation, but recommendations recommend it only for high-risk groups, due to its cost and the potential to lead to unnecessary medical procedures. Dr. Jessica Donington, a specialist in thoracic surgery, believes that current standards are no longer keeping pace with modern research, saying: “The standards are very limited.”

Until 2022, the guidelines recommend screening for people between 50 and 80 years old who have a long history of smoking, who still smoke or who quit less than 15 years ago. The recommendations were then expanded to include broader categories of current and former smokers, including those who quit smoking more than 15 years ago.

But the main US body for prevention recommendations has not evaluated new scientific evidence since 2021, even though the guidelines are usually reviewed every five years and were expected to be updated this year. No review has been announced yet, and the latest evidence assessment dates back to March 2025.

Myth 4: Screening does not save lives. Early studies in the 1990s and early 2000s showed that low-dose computed tomography (CT) detected lung cancer at earlier stages than conventional imaging or X-rays, but it did not significantly reduce mortality rates, which raised doubts about the utility of screening compared to its risks. But a study published in 2011, which included more than 50,000 patients, showed that the test reduces death rates by 20%, which strengthened the recommendation for its wider use.

Yang says that doctors today prefer to monitor suspicious pulmonary nodules and repeat imaging after a few months, rather than resorting directly to surgery. A biopsy is performed only in about 1% of cases, when the size of the node increases or its characteristics change.

Myth 5: Lung cancer only affects older people About one in ten patients newly diagnosed with lung cancer is under the age of 55. Women constitute 52% of new cases among those under the age of 40, and their percentage is higher among those who have never smoked.

The disease is often discovered in younger people at advanced stages, as many do not see doctors until symptoms appear, such as epileptic seizures or rib pain. The 20-year survival rate is 80% when lung cancer is detected early, compared to only 8% for five years when diagnosed at a late stage.

Myth 6: Symptoms begin with a cough. It is true that a persistent cough is a common symptom of lung cancer, as are shortness of breath, chest pain, unexplained weight loss, constant fatigue, and coughing up blood. But severe inflammation or neurological symptoms may also be early signs of the disease, especially in younger adults.

Myth 7: Lung cancer cannot be predicted. Yang believes that artificial intelligence models may outperform established guidelines in identifying people at high risk of developing lung cancer. Among them is the Cybil tool, which analyzes a single CT image to estimate the risk of infection over the next six years.

In 2023, its accuracy reached between 86% and 94% in determining the level of risk within a year. Dr. Lechia Seaquist explains that early detection aims to detect tumors when they are small, but their detection by imaging remains linked to the stage of their appearance in the images.

Cybil is an open source program used in research in more than 30 countries. Yang and Seaquist are preparing to study the possibility of using it to determine the level of risk in people who underwent imaging for other reasons, and then intensify testing for those most at risk of infection.