When many people think of an average lung cancer patient, they often picture an older man who smokes. But the face of lung cancer has changed. In the past 15 years, more women, never-smokers and younger people are being diagnosed with lung cancer.
In fact, lung cancer is the leading cause of cancer death in women, with more women dying each year from lung cancer than from breast, ovarian and colon cancer. The American Lung Association reports that while lung cancer rates have risen 79% for women over the past 44 years, they have fallen 43% for men. And for the first time in history, there are more young women than men with lung cancer.
As a thoracic oncologist at Sylvester Comprehensive Cancer Center, part of the University of Miami Health System, I’ve seen many younger women and never-smokers come into my clinic with a new diagnosis of lung cancer. Especially for people who never smoke, lung cancer is unexpected for both patients and their doctors, often leading to delays in diagnosis. Researchers have documented this trend of increasing lung cancer rates in women in different parts of the world and are beginning to understand why the number of cases is increasing.
Lung cancer in women
The first explanation for the rise in lung cancer rates among women is that many started smoking later than men, pushing back their peak in smoking-related lung cancer diagnoses.
Women also started smoking during the years when filtered cigarettes were most commonly used. This led to an increased risk of a cancer called adenocarcinoma because of the way cigarette filters spread tobacco smoke to the outer parts of the lungs. Some studies suggest that women are more susceptible to the carcinogenic effects of exposure to tobacco and cigarette smoke, including secondhand smoke, and may develop lung cancer after fewer years of smoking compared to men.
However, it’s important to note that most people who get lung cancer today are not active smokers. About 20% of women with lung cancer have never smoked – more than for men with lung cancer who have never smoked.
Risk factors for lung cancer
In addition to smoking and secondhand smoke, there are several other risk factors for lung cancer. These include a family history of cancer and exposure to asbestos, radon and air pollution.
Exposure to workplace carcinogens in the form of inhaled chemicals such as arsenic, beryllium, cadmium, silica and nickel is still a concern in some parts of the world. The potential risk of lung cancer from e-cigarettes and marijuana smoke is still being studied, but is potentially concerning.
Recently, researchers have also found that genetics may play a role in lung cancer risk in some patients with a strong history of lung cancer. Studies of these families have helped identify potential lung cancer susceptibility genes and environmental risk factors.
Like BRCA1 and BRCA2 in breast cancer, changes in genes that promote or protect tumor development may contribute to the development of lung cancer. Researchers have yet to identify specific mutations that may predispose individuals to lung cancer. However, studying familial genetic predisposition may help elucidate how lung cancer develops and lead to new biomarkers for early cancer detection in high-risk groups.
Lung cancer screening
In 2021, the United States Preventive Services Task Force updated its lung cancer screening guidelines to include younger patients with less smoking history. Now, lung cancer screening is recommended for adults ages 50 to 80 who have smoked at least one pack a day for 20 years, current smokers, and former smokers who have quit smoking in the past 15 years. Women at risk for lung cancer can talk to their doctor about ordering a low-dose CT scan for lung cancer screening.
Across the country, more than 70% of eligible women undergo breast cancer screening, but less than 6% of all eligible smokers undergo lung cancer screening. Researchers estimate that these new screening guidelines will increase the number of women eligible for lung cancer screening by 40% by including those at a younger age who are less exposed to smoking.
Lung cancer diagnosis
In recent years, an increasing understanding of the genetic changes that can lead to cancer and how the immune system can be harnessed to treat cancer has led to new targeted therapies and immunotherapies that have improved the prognosis of patients with lung cancer. Women generally have a better lung cancer prognosis than men, especially if they have never smoked and have tumors with molecular changes that can be treated with targeted therapies.
However, symptoms of lung cancer may not be recognized in women. Symptoms of lung cancer can include coughing, shortness of breath, overwhelming fatigue, and pain in the back, chest, or shoulder, which can be confused with other conditions. Because women are usually slightly younger at diagnosis than men, patients may be able to tolerate symptoms longer and delay seeking medical attention. Doctors may also not attribute these symptoms to lung cancer because of a patient’s younger age.
Recognizing the early symptoms of lung cancer, expanding eligibility for lung cancer screening, and testing for genetic biomarkers to select the best therapy are some of the steps that can help address the global epidemic of lung cancer in women .
This article was republished on The Conversation, an independent, not-for-profit news site dedicated to sharing ideas from academic experts. The Conversation is reliable news from experts, from an independent non-profit organization. Try our free newsletters.
It was written by: Estelamari Rodriguez, University of Miami.
Estelamari Rodriguez is affiliated with the University of Miami Health System. She receives funding from the American Cancer Society.