A new study found that fewer than 2 percent of heavy smokers in the U.S. get recommended lung cancer screenings, an imaging test that can catch tumors when they are small and potentially curable. Credit: Anette Linnea Rasmussen/Dreamsti | TNS

Sometimes you just don’t want to know, even when your life may hang in the balance.

A new study found that fewer than 2 percent of heavy smokers in the U.S. get recommended lung cancer screenings, an imaging test that can catch tumors when they are small and potentially curable. The numbers fall far short of screening for other types of cancer, including mammograms and colonoscopies-both procedures that are much more uncomfortable than the CT scan used to detect tiny tumors in the lungs.

[Maine among worst states for lung cancer, study finds]

Lung cancer is the leading cause of cancer death in the U.S., killing an estimated 150,000 Americans each year. For the past five years, such groups as the U.S. Preventive Services Task Force and the American Society of Clinical Oncology have urged people aged 55 or older who have smoked a pack a day (or the equivalent) for three decades or more to get checked for early stage disease. Medicare, the U.S. government’s insurance program for the elderly, pays for the procedure. None of it has made an impact.

“It’s still truly abysmal,” said Danh Pham, chief fellow of hematology/oncology at the University of Louisville’s cancer center in Kentucky, who will present the findings at the ASCO cancer meeting next month in Chicago. “We would like to make this a true call to action, whether it’s for more education or more research, to know why this disparity exists for lung cancer.”

It took a while for public health officials to start recommending routine lung cancer screening, because of questions about its accuracy and its ability to make a difference once the disease was detected. Subsequent studies confirmed the benefits for the heaviest smokers, with the use of screening intended for those most vulnerable to tumors.

The researchers analyzed registry data for everyone who underwent lung cancer screening in 2016 and found that 141,260 of the 7.6 million people eligible, or 1.9 percent, received it. By comparison, from 60 percent to 80 percent of eligible people get screening for breast, cervical and colon cancer, said Bruce Johnson, president of the American Society of Clinical Oncology and chief clinical research officer at the Dana-Farber Cancer Institute in Boston.

The testing shortfall could stem from primary care doctors’ failure to refer high-risk patients to one of 1,800 approved centers nationwide which provide the service. Psychological issues could also play a role, including fear of being diagnosed with a disease that smokers are constantly reminded of, Pham said.

“It’s very difficult to get patients to have this conversation with their doctors because of the stigma,” he said. “People may not want to know if they have lung cancer because it could confirm they’ve made bad lifestyle choices.”

Lung cancer deaths exceed those from breast, colon, pancreas and prostate cancer combined. There are very compelling reasons to get screened, said Johnson.

“If you screened the entire population of the U.S. who fit the criteria for having smoked enough and being the appropriate age, which is about 8 million people, you could save about 12,000 lives a year,” he said. “The majority of lung cancers picked up are early stage,” and finding them before the malignant cells spread reduces the risk of dying by about 20 percent, he said.

Johnson agreed with Pham that stigma, or even a sense among these smokers that they deserve cancer, may play a role in their avoidance of screening. It could also be a case of out-of-sight, out-of-mind: a belief among smokers that a diagnosis is a death sentence that would darken the rest of their lives.

Getting screened may not save your life, but it might help save someone else.

At its current rate, the screening is saving only 250 lives a year, Johnson said. More than half of patients who are diagnosed when the disease is still contained within the lungs survive for at least five years, compared with just 4 percent of those with stage IV cancer that has spread to other organs, according to the American Cancer Society.

While there have been breakthroughs that extend the lives of those suffering from advanced lung cancer, including powerful drugs such as Merck & Co.’s Keytruda and Bristol-Myers Squibb’s Opdivo, the benefits of screening are reaped by people before their bodies are ravaged by the disease, Pham said.

“The whole point of screening is to find cancer at early stages, when patients can still undergo a lifesaving treatment such as surgery,” he said. And not every smoker should undergo the imaging, which is reserved for the highest-risk patients, he said. since it’s possible to get a false positive result.

The 2016 screening rates of eligible smokers, by U.S. region:

— West: 1 percent

— South: 1.6 percent

— Midwest: 1.9 percent

— Northeast: 3.5 percent

The good news, Pham added, is that there does appear to be a slight increase in screening for last year. The impact of finding lung cancer early goes beyond saving individual lives, said Monica Bertagnolli, chief of surgical oncology at Dana-Farber and the incoming president of ASCO.

“Our ability to develop new, preventive therapies is directly dependent on our ability to screen high-risk populations,” a process that has found some success in breast, colon and cervical cancer, she said. “If you can’t do it for lung, it hampers forward progress.” In other words, getting screened may not save your life, but it might help save someone else’s.

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