With smoking rates declining, so too are lung cancer deaths. For nonsmokers, the numbers tell a different story.

November is Lung Cancer Awareness Month, which brings both good news and bad. On the one hand, overall rates of the disease — and deaths from it — have declined precipitously as smoking rates have plummeted. But, on the other hand, diagnoses are climbing among people who have never smoked.

The lung cancer landscape in the U.S. has shifted considerably since the first surgeon general’s report linking the disease to smoking was published 60 years ago last January, so we’ve broken down emerging trends with the help of three charts. Here’s what to know about lung cancer in 2024.

Lung cancer diagnoses are less common and less fatal

It’s hard to overstate the progress the U.S. has made against lung cancer. The disease’s mortality rate has declined by 35% for men and 26% for women over the past 10 years, according to the American Lung Association (lung cancer rates have always been, and still are, considerably higher among men, which partially explains why mortality has fallen more steeply among males). And the rate of new cases has fallen over the past decade too, by 23% for men and 11% for women.

Much of this encouraging shift is thanks to a parallel trend: Smoking rates have declined too. Undoubtedly, better screening and innovative treatments have saved or prolonged many lives. But smoking is linked to between 80% and 90% of lung cancer deaths in the U.S., the Centers for Disease Control and Prevention estimates. If cigarettes were as popular now as they were in the ’60s, even the most cutting-edge treatments would struggle to put a dent in the mortality rate.

However, not everyone who smokes develops lung cancer, and not everyone who is diagnosed with lung cancer has smoked, ever or heavily. “Lung cancer is different in people who never smoked,” Dr. Heather Wakelee, a Stanford University professor of oncology who specializes in lung cancer, tells Yahoo Life. “But the people who have smoked start to feel like they’re being blamed” for the disease, she says.

Lung cancer in people who haven’t smoked is stubbornly high

The CDC estimates that between 10% and 20% of people who develop lung cancer in the U.S. don’t have a history of smoking. “It’s hard to tease out” precisely what causes these cases, Zach Jump, director of research, epidemiology and statistics at the American Lung Association, tells Yahoo Life. Likely contributors include air pollution, genetics and radon gas (which the Environmental Protection Agency has blamed for as many as 21,000 lung cancer deaths, though experts say that’s likely an overestimate). “But right now, there are more questions than answers,” says Jump.

Whatever the case may be, there has been little change in the deadliness of the disease for people who don’t have a history of smoking. Lung cancer was responsible for more than 25,000 deaths that couldn’t be attributed to smoking in 1990, according to a study published in the Journal of the National Cancer Institute. In 2018 that figure was stable at 27,000 (accounting for population growth). As smoking rates have fallen, lung cancers in people without a history of smoking account for a growing proportion of annual diagnoses.

Different kinds of lung cancer tend to strike those who haven’t smoked

There are two broad groups of lung cancers, as well as subgroups:

• Small-cell lung cancer, which is diagnosed overwhelmingly among people who have smoked, per Cleveland Clinic. These tumors grow more quickly and typically originate from cells in the bronchi or windpipe.

• Non-small-cell lung cancer (NSCLC) is much more common, accounting for about 85% of lung cancers and originating in the lung tissue. It has several subtypes:

  • Adenocarcinoma is the most common subtype of lung cancer among people who have and haven’t smoked alike, but it’s the form most often seen in people without a smoking history. It begins around the outside of the lungs.

  • Squamous cell carcinoma originates in the lining of the lungs and is the second most common form of lung cancer. It’s more closely linked to smoking than other forms of NSCLC.

  • Large-cell carcinoma, the least common subtype, grows and spreads more aggressively than other forms of lung cancer. Smoking is thought to be its predominant cause.

Why are rates staying higher for people who never smoked?

Asian heritage has emerged as a major risk factor for developing lung cancer despite never having smoked. People with Asian ancestry are more likely than other groups to be diagnosed with tumors that have a mutation to a protein called epidermal growth factor receptor. “About 50% of nonsmoker Asians have this mutation, compared with less than 20% of non-Hispanic white people” with lung cancer, Dr. Bryant Lin, a professor of primary care at Stanford Medicine and co-founder of the school’s Center for Asian Health Research and Education, tells Yahoo Life. (Lin was diagnosed with this form of lung cancer himself.) What’s not clear yet is why this occurs.

Wakelee (who is also Lin’s oncologist) is among the leading researchers working on that very question, looking at other sources of indoor smoke, like cooking oils, as possible contributors. And, we now have quite “clear data that air pollution is playing some role,” she says. Some of the best data on lung cancer, smoking and pollution comes from Taiwan. “Women in Taiwan almost never smoke, and rates of smoking in men have come way down, but when you look at lung cancer there ... squamous [a type closely linked to smoking] rates are way down and rates of adenocarcinoma [the form nonsmokers tend to get] are way up,” Wakelee explains.

The U.S. has less and lower-quality data on smoking, she says. But similar trends are apparent. Even as rates of other forms of lung cancer (and deaths due to them) have come down, adenocarcinoma rates have remained persistently higher.

What you can do

First and foremost, not taking up smoking, or trying to quit if you already smoke, is the No. 1 thing you can do to reduce your risk (and improve your overall health), experts say. If you don’t know if your home was radon-tested, it’s worth having that done, as the radioactive gas is a carcinogen known to raise risks of lung cancer. That’s especially true if you live in certain parts of the country, like the northern Midwest and Mountain West, says Wakelee. States where radon is more prevalent include Montana, Pennsylvania and South Dakota. And while pollution in your vicinity isn’t under your direct control, Wakelee says it’s worth advocating for better air quality in your community and with your vote.

Finally, don’t ignore symptoms or avoid or delay screening, Jump urges. Signs of the disease include a new and persistent cough, shortness of breath, coughing up blood and, in some cases, chest or upper back pain. But one of the problems of lung cancer is that signs often develop only at the disease’s later stages. That’s why screening — which is recommended between ages 50 and 80 for those who smoked one pack a day for 20 years or two a day for 10 years, or who have been a smoker in the past 15 years — is so crucial. “Formerly, it was a death sentence, so people don’t want to know; if they think they’ll be at risk they want to put their head in the sand,” Jump explains. “But screening offers incredible hope.” Now surgery for lung cancer that hasn’t spread can be “essentially curative,” he explains. And, for those diagnosed in later stages, treatments have come an incredibly long way.