Screening for lung cancer saves lives, but many aren’t aware it’s an option. Here’s what people who face a high risk of the disease should know.
Screening for lung cancer in high-risk individuals saves lives by detecting disease at an early stage when it’s likely curable with surgery, without the need for drugs or radiation — or the side effects they can generate.
While 8 to 9 million people in America are eligible for screening via low-dose computed tomography (CT) due to their smoking history, nationwide, only 4% of them have participated, says Dr. Andrea McKee, a radiation oncologist who runs the lung cancer screening program at Lahey Hospital and Medical Center in Burlington, Massachusetts and volunteers as a spokesperson for the American Lung Association.
That level of participation pales in comparison to the screening rates for other cancers, McKee says: In Massachusetts, which holds the record for lung cancer screening with 12% of high-risk individuals participating, 75% of those eligible for colorectal screening get it, and an even higher percentage of eligible women get mammograms to check for breast cancer.
One reason for the low participation rate among people at risk for lung cancer is that the screening test for the disease is fairly new, and another is that awareness about it is low among patients and sometimes their doctors, McKee says.
ALA is determined to help change that.
On its website’s homepage (lung.org), the ALA encourages visitors to consider screening. It offers a quick quiz that tells people whether they are eligible, as well as a list of conversation points for qualified patients to bring up with their doctors. Furthermore, McKee says, “The ALA has recommended that organizations reach a goal of screening at least 20% of those eligible by 2025.”
Her own institution has more than complied, having screened 65% of its eligible population, about 6,000 patients, since the test became available in 2011.
“It’s doable, but it requires education, effort and outreach into the community and to primary-care doctors,” she says.
EVIDENCE SUPPORTS SCREENING
Low-dose CT screening combines X-ray and computer components to image the inside of the chest. It employs less ionizing radiation, which can damage cells and cause them to malfunction, than a conventional CT scan.
The technique “has been proven to significantly reduce mortality due to lung cancer and is one of the greatest advances we’ve been able to achieve in the fight against an otherwise very deadly disease,” McKee says.
Clinical trials of the test found a mortality benefit — or reduction in the rate of death — between 20% and 60%, which McKee described as “huge.”
The National Lung Screening Trial, concluded in 2011, gave one group of patients an annual low-dose CT of the chest while another got an annual chest X-ray in three rounds of screening over two years. After six years, the researchers followed up and found that there had been
20% more deaths in the chest X-ray group compared with the CT group. There were 247 deaths from lung cancer per 100,000 person-years in the low-dose CT group and 309 deaths per 100,000 person-years in the radiography group. A person year is a measurement that takes into account the number of people in a study and the amount of time each one participates. These results show “that low-dose CT saves lives,” McKee says.
In Europe, the Nelson study compared low-dose CT of the chest against no intervention. Four screens were conducted over 5 1/2 years, and in a follow-up 10 years later, the CT group was found to enjoy a 25% mortality benefit across the board (2.5 deaths per 1,000 person-years in the CT group versus 3.3 deaths per 1,000 person-years in the no-intervention group); when only the study’s women were looked at, the CT group was determined to have experienced a 60% mortality benefit.
And the MILD trial, which compared the effectiveness of a pulmonary function test with or without CT, found a 40% mortality benefit for those who got CT scans. That broke down to 247 deaths per 100,000 person-years in those who received CT scans versus 309 deaths per 100,000 person- years in the chest radiography arm. McKee explained the results she’s seen in her own experience screening patients.
When screening for the first time, she’s found that cancers show up in 2% to 3% of patients, 70% early stage and 30% later stage. After that, these patients develop lung cancers at a rate of 1% to 2% per year, and with continued annual screening, 90% of them are caught in an early stage.
This is important because “stage 1 lung cancer has an 88% chance of cure,” McKee says. “Compare that with stages 3 or 4, whose five-year survival rates are less than 35% and 5%, respectively.”
The experience of being treated for an early-stage cancer is also less grueling, she noted. While treatment for stage 1 or 2 lung cancer typically consists of surgery alone, treatments for stage 3 or 4 disease may include radiation, chemotherapy, targeted drugs and/or immunotherapy.
Those eligible for screening have histories of heavy smoking. “Almost all guidelines support screening of patients over age 55 with a 30 pack-year history of smoking who currently smoke or quit within the past 15 years,” McKee says. Pack years are measured by multiplying the average number of packs a person smoked per day by the number of years they smoked.
“What is argued over is whether the screening should stop at age 77 or 80,” she says. “The United States Preventive Services Task Force recommends screening until age 80, while the Centers for Medicare & Medicaid Services recommend screening until age 77.
The National Comprehensive Cancer Network takes a broader approach, recommending screening for patients 50 and over with a 20 pack-year history of smoking and no upper age limit, but patients must have one other risk factor for lung cancer, such as first-degree family history or personal history of lung cancer, history of a tobacco-related cancer, non-carcinogenic exposure or a history of COPD or interstitial lung disease.”
It’s possible that guidelines could change, McKee says: The USPSTF is considering whether there’s value in screening another high-risk population based on data from two randomized controlled trials published since its last review. The studies included people age 50 and older with somewhat lighter smoking histories compared with those enrolled in previous trials.
Under the Affordable Care Act, annual lung cancer screening is free to high-risk individuals through health insurance, but insurers may use varying guidelines to determine who is eligible.
“The issue is if there’s additional testing recommended as a result of the screening test,” McKee says. “If it shows a finding that requires a three- or six-month follow-up scan, that might be subjected to a deductible.”
She adds that some screening programs are free for the uninsured or underinsured, although not widely available.
“If we were to discover lung cancer,” she says, “most hospitals can work with a patient to get emergency coverage in place.”
REASONS FOR UNDERUSE
With screening available, why do so few take advantage of it? “The Centers for Disease Control just reported that nine out of 10 eligible people are not aware of the recommendations for testing,” McKee says.
One reason is that the test is so new. Although the study that established the benefit of screening was published in 2011, “until 2015 there was almost no way of being able to charge for the test — there was no billing code for insurance companies to use,” she says. During that period, most of the scans conducted were done for free or at a reduced charge by hospitals, including Lahey.
“We did it as a mitigating effort to level the playing field, because if you were a patient at high risk and wanted the test, it could cost $1,000 out of pocket,” McKee says.
She added that a stigma, or blame, associated with lung cancer because many cases are linked with smoking could be another a reason there isn’t more enthusiasm around the idea of CT screening to detect the disease.
“If we were to find a tool that reduced the mortality benefit 20% to 60% in breast cancer or other cancers that perhaps aren’t as stigmatized as lung cancer,” McKee says, “we may not be seeing some of the challenges we’ve been seeing. We need to deal with the stigma associated with this diagnosis to help drive this forward.”
SAFETY AND EFFECTIVENESS
In addition to being simple — patients are asked to hold their breath for 10 seconds and don’t even need to change into a gown — low-dose CT screening is quite safe, McKee says.
“The test uses about as much radiation as a mammogram, and we’ve been treating with that for many decades with no proven increased risk to that population, which is similar in age to the group at risk of lung cancer,” she says.
She adds that patients don’t need to worry about a high rate of false-positive results (positive scans that lead to normal biopsies or no subsequent lung cancer development) associated with CT screening for lung cancer. Despite widely misreported numbers in 2011, the rate is reasonable, she says.
“The actual rate is 9% to 10% in the first year of screening, because we have nothing to compare the results against, and 5% after that, and that’s very comparable to what we
see with mammography,” she says. “This, too, may have to do with bias about screening in this patient population. It’s been reported wrongly, and we’ve been working to get it corrected.”
GETTING THE TEST
Those interested in getting screened should know that most hospitals have or are developing lung cancer screening programs, and that there are centers in every state conducting the tests, some of which are listed on the ALA’s website. There are even mobile CT units in some under- served states.
“Patients should check out ALA site, take the quiz, find out if they meet the high-risk criteria and arm themselves with information so they can have a conversation with their physician,” McKee says. “They shouldn’t be surprised if the doctor is not fully informed of the new data, so being proactive and advocating for themselves is a good thing.”