That's one of the findings from a new American Lung Association (ALA) survey of over 1,000 adult U.S. women.
The poll also found that many women may not appreciate the lung cancer risk to nonsmokers. And few were aware of just how deadly lung cancer remains, in a time of major progress against some other cancers.
According to Alana Burns, vice president of the ALA's Signature Cause Campaign, the poor survival rate may be one reason that lung cancer is not on women's radar.
"With breast cancer, there are so many survivors out there telling their stories and advocating," Burns said. "But more than half of women diagnosed with lung cancer are gone within a year. There is no legion of survivors talking about their experiences."
In the United States, breast cancer is the most common cancer among women, followed by lung cancer. But lung cancer is the top killer. According to the U.S. Centers for Disease Control and Prevention, lung cancer kills about 38 out of every 100,000 U.S. women each year. The death rate from breast cancer is 22 per 100,000.
But when the ALA survey respondents were given a list of cancers and asked to pick the top killer of women, 51 percent chose breast cancer. Only 22 percent chose lung cancer.
"It's pretty clear that breast cancer gets more press," said Dr. Subhakar Mutyala, associate director of the Scott & White Cancer Institute in Temple, Texas.
Plus, he said, since there's routine screening for breast cancer, women and their doctors are talking about the disease.
But unless you're a smoker, your doctor is probably not going to bring up lung cancer, noted Mutyala, who reviewed the survey findings. And while it is possible to screen for lung cancer, he added, that's limited to certain high-risk groups.
Right now, the U.S. Preventive Services Task Force recommends annual CT scans for adults aged 55 to 80 who currently smoke or who quit within the past 15 years -- and smoked for at least 30 "pack-years." That means one pack per day for 30 years, or two packs a day for 15 years, for example.
Smokers are not, however, the only people who get lung cancer. About 10 percent of people diagnosed with the disease never smoked, the ALA states.
But half of the women in the new survey said they were "not concerned" about lung cancer because they'd never smoked. That included 68 percent of lifelong nonsmokers.
"Many people think of lung cancer as solely a smoker's disease," Burns said.
Yet, she added, if lung cancer in nonsmokers were considered its own disease, it would rank among the top-10 cancer killers in the United States.
Burns and Mutyala said people should be aware of the risk factors for lung cancer in nonsmokers.
The top cause is exposure to radon gas, which can become concentrated in homes that are built on soil with natural uranium deposits. Other risk factors include chronic exposure to secondhand smoke or air pollution, and on-the-job exposure to pollutants such as diesel exhaust and asbestos. Researchers have also found gene mutations that play a role in some lung cancers.
The prognosis for people with lung cancer remains grim, according to the lung association. Less than half of women with the disease are still alive one year after they're diagnosed -- a statistic few women in the survey said they'd heard before.
Unfortunately, the cancer is usually diagnosed at a late stage. "Only about 20 percent of lung cancers are operable when people are diagnosed," Mutyala said.
To help improve that outlook, the ALA wants the U.S. National Institutes of Health to boost its funding for lung cancer research -- from the current level of $213 million per year, to $400 million by 2025. By comparison, current funding for breast cancer research tops $650 million a year, according to estimates from the U.S. National Institutes of Health.
"That's despite the fact that lung cancer kills more people than breast, prostate and colon cancers combined," Mutyala said.
Burns said women can help by getting involved in efforts to raise awareness and funds. The ALA just launched a new website, dubbed Lung Force (lungforce.org), where people can find information on local charity events, share stories about their experiences with lung cancer, and get information on the disease.
"We want people to learn about the risks," Burns said. "This is something that's relevant to you. You should care."
The American Lung Association has facts and figures on lung cancer.