Six years ago, Donna Gaidamak was diagnosed with stage 4 lung cancer, but that hasn't stopped her from living a full life.
A 10-minute test could save 10,000 lives? A big number and a big claim, but many physicians believe that catching lung cancer while it’s small could mean something big.
Low-dose computed tomography, commonly called a CT scan, is a 10-minute test that is becoming more widely used. Research shows that it detects cancer early, but many experts believe plans to deploy it on a national scale may be premature.
“It’s a big deal because lung cancer itself is a huge epidemiological problem, “ said Dr. Edgar Chedrawry at thoracic surgeon at Weiss Memorial Hospital in Chicago. “We have an epidemic of lung cancer.”
Though lung cancer is not the most commonly occurring cancer, it is the deadliest. According to the American Cancer Society, more than 160,000 patients die every year of lung cancer—more than breast, prostate and colon cancers combined.
“We never had a real scientific reason to say get screened, now we do,” Chedrawry said.
He was referring to the National Lung Screening Trial, an extensive randomized trial conducted between 2002 and 2004. During that time, more than 50,000 people at high risk for lung cancer received annual screening with either low-dose CT scans or chest X-rays at 33 U.S. medical centers.
In 2011, the New England Journal of Medicine published the results from the trial. The data showed that the rate of positive screening tests was 24.2 percent with low-dose CT compared with 6.9 percent with radiography, and mortality from lung cancer decreased with low-dose CT screening by 20 percent.
These numbers have prompted some hospitals across the country to increasingly offer lung cancer screening programs—but is the test ready for primetime?
“[The trial] was on a scale that you don’t always see in this kind of research. It’s hard to say whether [the reaction] is normal or not,” said Amy Copeland, a spokeswoman for the Lung Cancer Alliance, a Washington, D.C.- based advocacy organization. She said that though the trial results were released in 2011, research about low-dose CT scans has been going on for years, and other studies were published even before the National Lung Screening Trial came out.
With these programs expanding and the scans becoming more widely accepted questions arise about for whom the screenings are intended and who should have to pay for them.
In December 2013, the U.S. Public Services Task Force, a national panel of prevention experts, found beneficial evidence based on the NLST’s results and issued a “B” recommendation for lung cancer screening. The task force’s guidelines defined whom screening is recommended for, while the “B” grade clears the way for insurance coverage for patients under that category.
The task force recommended annual low-dose CT screening for people aged 55 to 80 years who have a 30 pack-year smoking history and smoke, or have quit smoking within the past 15 years. A pack-year equals the number of packs smoked per day multiplied by the number of years, meaning a person smoked either one pack daily for 30 years or two packs for 15 years.
For the high-risk patients who are insured and want to get screened, the “B” rating is big news because under the Affordable Care Act, a B rating from the task force recommends that insurers to cover the costs of low-dose CT scans.
Copeland said groups like the task force have found adequate evidence to support the trial’s conclusions, but not every group gives lung cancer screening a good grade. “Other organizations look at that same evidence and come to different conclusions.” Copeland said.
In January, another medical organization, the American Academy of Family Physicians gave low-dose CT lung cancer screening an “I” recommendation, for “insufficient evidence.” The academy, which comprises more than 100,000 members, called for more screening trials and discussion between doctors and patients about the potential benefits and risks of screening.
Concerns surrounding lung screening include risk of radiation, extent of follow-up procedures and price, but the biggest criticism is overdiagnosis.
Because low-dose CT scans are more sensitive than chest X-rays, the trial showed they had a higher rate of false-positive results; around 18 percent of lung cancers detected by screening were overdiagnosed. This means a patient may be diagnosed, go through treatment—and experience the anxiety that comes with it— only to find out the tumor was not life-threatening all along.
“The biggest fear of any screening test is we’re going to overdiagnose people,” conceded Chedrawry, “that we’re just picking [nodules] up early, but the mortality and longevity hasn’t changed or we’re having a lot of false-positives.”
A common occurrence with other cancers, Jeffery Borgia, a medical researcher at Rush University Medical Center in Chicago said that the overdiagnosis question is less pressing with lung cancer because of the compressed timeline of the disease. According to the National Cancer Institute, the percentage of people who survive five years with lung cancer is 16.6 percent, but when diagnosed late that number is much lower. Over half of lung cancer cases are diagnosed at stage 4, making the ability to accurately identify tumors earlier more urgent for researchers like Borgia, who said,
“How we manage those nodules they find is kind of the big question right now”
What's next for screening?
With worries of overdiagnosis and cost-effectiveness looming, oncologists’ current efforts are focused on developing companion tests for low-dose CT scans that could be conducted more than once a year.
Borgia explained that biopsies have risk associated with extracting tissue from lungs, so researchers are working to develop blood tests that could be conducted more often than a low-dose CT scan and at fraction of the cost.
Right now, the cost of a low-dose CT scan varies from hospital to hospital, ranging from free to $450, with the average usually around $250. Because of the task force’s rating, these scans will be covered under the Affordable Care Act, but most lung cancer patients are older than 65.
Currently, the U.S. Centers for Medicare & Medicaid Services is evaluating the recommendation for screening and will determine in April whether Medicare will also cover the scans. If, the centers approve, then Medicare will be required to pay for low-dose CT scans. Last week, the American College of Radiology, the Lung Cancer Alliance, the Society of Thoracic Surgeons, and 38 other medical organizations urged the centers in a letter to provide coverage for high-risk patients.
As research and policy continue to develop, medical communities must weigh what they know with what they don't, but most doctors hope that better screenings can lead to better care for lung cancer. Dr. Thomas Hensing, a thoracic oncologist at Evanston Hospital, explained that as screening improves, it gives physicians a target for earlier treatment.
“I think it can have a very significant impact. The trial that’s been reported is proof of the principle that screening can work,” he said. “There are obviously risks associated with screening that need to be addressed between physicians and their patients, but the fact that we’re going to start seeing more screen detected cancers I think is going to be a helpful thing in the long-term.”