“Lung cancer”—what first pops into your head when you hear that?
For many people, the answer is “smoking.” Lung cancer has been considered a smoker’s disease until recently. The stigma that comes from the association—that people who have lung cancer must have brought it on themselves—possibly contributes to the disease’s high rate of mortality.
Lung cancer remains the second most common cancer in men and in women in the United States, trailing behind prostate cancer for men and breast cancer for women.
According to the National Cancer Institute, of all new cancers that were expected to be diagnosed in 2018, 13.5% (or 234,030 cases) were estimated to be lung cancer.1 In addition, 154,050 patients were estimated to die from lung cancer in 2018, roughly a quarter (25.3%) of all cancer-related deaths in the United States that year, making it the number one cause of death from cancer in the United States.1
The Lung Cancer Stigma
The main reason lung cancer is difficult to treat is because it is typically diagnosed late, when the disease has developed to an advanced state (stage III or IV) or has spread (metastasized) in the body. According to the Cancer Treatment Centers of America, about one-third (30%) of patients with lung cancer are diagnosed at stage III, and even more people (40%) are diagnosed at stage IV, when the cancer has metastasized.2
Before 2011, oncologists mainly used x-ray to diagnose lung cancer, which often fails to detect early-stage lung cancer. That changed in 2011, when results of the National Lung Screening Trial (NLST) became available for the first time. The NLST, which was conducted by the National Cancer Institute, was the first evidence to demonstrate the benefit of a low-dose chest CT rather than an x-ray to detect lung cancer early in patients who are at increased risk for this cancer.3 However, the results of the study are still being analyzed and screening recommendations are different for different people based on their risk level.
The NLST study showed that early-stage lung cancer was more likely to be picked up by a low-dose CT scan than by an x-ray, which reduced the deaths from lung cancer by 20% in people at high risk for this cancer. Despite these results, only 2% of high-risk patients have been taking advantage of CT testing, according to this study. Why so few people?
“We don’t really understand why patients don’t get screened, but we think the stigma of smoking in anti-tobacco campaigns plays a large part,” Elizabeth David, MD, Associate Professor of Clinical Surgery at the University of Southern California’s Keck School of Medicine, said in an interview about smoking and lung cancer, noting that the anti-smoking campaigns help to reduce lung cancer cases, but they have also led to an unfortunate stigma for those who are diagnosed with lung cancer.
“The unintended side effect of those campaigns is their negative influence on patients’ decisions to pursue symptoms when they have them, or their willingness to undergo treatment. In addition, although we don’t understand this fully, this stigma likely influences doctors and the treatments they offer to patients,” Dr. David said.
Another finding of the NLST study was that people who remained tobacco-free for 7 years also benefited from a lower risk of dying from lung cancer. Patients who were diagnosed with lung cancer but quit smoking before their treatment started also improved their chances of survival.
Know Your Risk Factors
Patients with lung cancer are divided into 2 camps. Smokers represent about 80% of people who are diagnosed with lung cancer, but about one-fifth (20%) of lung cancers affect people who have never smoked, according to Patricia Rivera, MD, of the University of North Carolina Lineberger Cancer Center. Moreover, that number continues to rise, although the reasons for that are unclear, Dr. Rivera said in an interview.
Therefore, people who have smoked (or are still smoking) should get familiar with their risk factors for lung cancer to decide if they should be tested for lung cancer. According to Dr. David, these risk factors include:
- Being between age 55 and 80, and having smoked more than 1 pack a day for 1 year, or 1/2 a pack a day for 2 years
- Having an immediate family member who has died from cancer
- Exposure to environmental toxins, such as asbestos or radon.
However, there are no specific risk factors for nonsmokers to know when to get screened for the genetic mutations that can cause lung cancer. There are no signs of these mutations that can suggest to people to get screened for lung cancer.
In an interview with Viswam S. Nair, MD, of the Moffitt Cancer Center in Florida, Dr. Nair said that among people who are nonsmokers, more women than men have lung cancer, and women with an Asian background are particularly at risk for lung cancer associated with a genetic mutation. In addition,
African-American men who are nonsmokers have a higher risk for lung cancer than do nonsmoking white men, according to Dr. Nair.
“The reason for this is unclear,” Dr. Nair said. “We’re trying to understand the genetic predisposition to lung cancer, and we’re seeing more cases in nonsmokers than in the past.”
Patients with or without a history of smoking are encouraged to see their primary care physician if they have a persistent cough, shortness of breath, or a respiratory ailment that won’t go away. Because lung cancer has no symptoms until late in the game, it is difficult to detect it early, which is why screening may be a good idea.
Until the cancer invades the tissue surrounding the lungs, such as the heart and its blood vessels, patients typically won’t notice any symptoms and will not consult their doctor.
This means that persons at risk must hurdle the stigma associated with lung cancer and get screened. Furthermore, they should pay attention to the hodgepodge of symptoms that may indicate that something has gone awry.
People who act on their risk factors, primarily older age and a history of smoking, still have to overcome another barrier—getting proper testing, because the guidelines for testing are not always followed. For example, breast cancer screenings are relatively straightforward; if you are 40 years or older, you get a mammogram once a year. However, patients with risk factors for lung cancer have to “push” their primary care doctors for a chest CT scan, because the current standard for screening is relatively new, and most doctors will order an x-ray and not a CT scan to detect lung cancer.
The Downside of Testing
The benefits of better and earlier testing come with a cautionary note. CT scans can show false-positive results, meaning they can show the person has lung cancer when there is no lung cancer. This leads to additional testing and biopsies of the suspected lung tissue, which are not needed and can cost extra money, not to mention the unnecessary anxiety to the person.
“We’ve learned a lot of things from overtesting with prostate and breast cancers in the past,” Dr. Rivera said. “Patients with benign tumors were being treated when they didn’t have to be. We’re trying to be more prudent with our treatment strategy for lung cancer.”
As CT scan testing becomes more refined, doctors will be able to separate cancerous lesions from benign tissue correctly, which will prevent unnecessary additional testing and treatment. For patients without high risk factors, genetic testing—although not yet being used for screening—may be the way of the future.
- National Cancer Institute. Cancer stats facts: lung and bronchus cancer. 2019. https://seer.cancer.gov/statfacts/html/lungb.html.
- Cancer Treatment Centers of America. Lung cancer. 2019. www.cancercenter.com/cancer-types/lung-cancer/stages.
- National Cancer Institute. National Lung Screening Trial: questions and answers. November 12, 2014. www.cancer.gov/types/lung/research/nlst-qa.
- Lung cancer remains the second most common cancer in men and in women in the United States
- Lung cancer is difficult to treat, because it is typically diagnosed late
- People who have never smoked can have lung cancer because of a genetic mutation
- There are no specific signs for nonsmokers to know when to be screened for the genetic mutations that can cause lung cancer
- It’s often a good idea to get screened for lung cancer, because usually there are no symptoms until late in the game
- Patients with or without a history of smoking should visit their primary care doctor if they have a persistent cough, shortness of breath, or a continuing respiratory problem
- A major study showed that early-stage lung cancer was more likely to be picked up by a CT scan than by an x-ray
- However, CT scans can show false-positive results, meaning they can show lung cancer when there is no lung cancer
- Patients who quit smoking before treatment started improved their chances of survival
Cancer Treatment Centers of America
National Cancer Institute
National Lung Screening Trial