Shots - Health News
Mon July 29, 2013
Panel Urges Lung Cancer Screening For Millions Of Americans
Originally published on Thu August 22, 2013 12:24 pm
A federal task force is planning to recommend that millions of smokers and former smokers get a CT scan annually to look for early signs of lung cancer.
The 16-member US Preventive Services Task Force gives that lung cancer screening test a grade of B, which puts it on the same level as mammography for women between the ages of 50 and 74.
That grade is important, because preventive tests with a grade of A or B oblige Medicare, other federal health programs and private insurers to cover the entire cost, beginning a year after a guideline is adopted. A lung scan costs about $300 to $500.
"This is the first time we've had science that tells us that we can actually avoid some lung cancer deaths through screening," task force vice chairman Michael LeFevre tells Shots. "So this is really a big change."
It's a change that some won't welcome. Some experts warn that it's going to cause too much follow-up testing for many patients, with the accompanying anxiety. Another concern is that screening will uncover many cancers that would never have caused a problem – a phenomenon called overdiagnosis.
The task force estimates that its proposed recommendation will cut U.S. lung cancer deaths by 20,000 a year. That's only about 13 percent of the nearly 160,000 people who die of the disease in this country annually.
"That's a relatively small proportion of those 160,000 deaths," LeFevre acknowledges. The problem is that even with screening, many people's lung cancer will be too advanced for effective treatment. "But a small proportion of a big number is still a big number," adds LeFevre. "And 20,000 lives is a lot of people."
Under the panel's proposal, screening is expected to save one life for every 320 people screened. By comparison, it takes 900 to 1,900 mammograms to save one life from breast cancer (depending on whether those screened are older or younger). And LeFevre estimates that it takes about 500 colonoscopies to save a life from colon cancer.
The task force will consider comments on the proposed guidelines before issuing a final recommendation in three to six months, LeFevre says.
Tom Murphy, a 61-year-old Maryland man, has no doubt that annual screening prevented him from dying of lung cancer as his father did.
Murphy, who smoked for three decades, started getting yearly lung scans in 2005 as part of a study. Five years later, a scan showed that a spot on his right lung was growing.
"Oh absolutely, that scan saved my life," Murphy tells Shots. "This thing started at five millimeters in January of 2010 and at the point they took it out, it was 1.2 centimeters, nine months later. So I'm very grateful. And I believe to this day that it saved my life."
The proposed recommendation is aimed at people who are at especially high risk of lung cancer. They're between the ages of 55 and 79 and they have smoked the equivalent of a pack of cigarettes a day for 30 years or more. If they have quit smoking, it must be within the past 15 years. After that, people have gained enough benefit from not smoking that screening isn't useful, the panel says.
Nearly 90 million Americans are smokers or former smokers. About 7 million of these are in the target age group and have smoked at least a pack a day for 30 years.
The Task Force is trying to strike a crucial balance – what LeFevre calls "the point at which (the screening tests) seems to do a significant amount more good than harm."
A fundamental problem with lung cancer CT screening is that when it finds a suspicious-looking nodule in a lung, it turns out to be non-cancerous 96 percent of the time. That's called a false positive rate, and it may be higher than any other approved screening test.
Most people who have a positive scan would be scheduled for a second scan several months later to see if the nodule has grown. If it has, the patient may need further scans, a biopsy of tissue through a needle inserted into the lung, or even lung surgery.
"We are actually going to do some lung surgery on people just to prove that they don't have cancer," LeFevre says.
He says people who have an abnormal lung scan are going to have to be calm, patient and deliberate – and their doctors are too.
"This is an anxiety that I have about lung cancer screening," says LeFevre, who is an associate professor of family medicine at the University of Missouri.
"If somebody hears they have a 5 percent chance that this is cancer, and then you say, 'Well, let's wait three months and repeat your CAT scan,' if the emotional response is, 'No, let's do something now," then we're going to do a lot of harm in the process of doing a little good," LeFevre says.
Dr. Kenneth Lin of Georgetown University thinks the task force is putting too much faith in lung screening.
"They rank it with those tests that your doctor – if they're a good doctor – is supposed to bug you about to get done," Lin says, referring to mammograms, colonoscopy and Pap smears. "And I don't feel that this test necessarily meets that criteria. I don't necessarily feel that patients should be pressured into getting this test done."
He and others worry not only about the high false-positive rate and the ensuing medical tests, but also what doctors call "overdiagnosis" – the discovery of cancers that would never become a problem.
"Uncovering this reservoir of indolent disease will almost always happen when you start screening," Dr. Laura Esserman, a breast cancer specialist at the University of California San Francisco, tells Shots. "We need to recognize it and understand it. Because if you don't, you're going to overtreat people."
Esserman is coauthor of a commentary on overdiagnosis and overtreatment of cancer published online Monday by JAMA, the journal of the American Medical Association.
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A federal task force is planning to urge millions of smokers and former smokers to get an annual test that looks for early signs of lung cancer. The proposal was released today by the Annals of Internal Medicine. The panel is convinced that the test, a computerized X-ray scan, will save tens of thousands of lives. But as we hear from NPR's Richard Knox, the screening has some important downsides.
RICHARD KNOX, BYLINE: The U.S. Preventive Services Task Force says its proposed recommendation will prevent 20,000 Americans a year from dying of lung cancer. Dr. Michael LeFevre, a vice chairman of the panel, acknowledges that's only about 15 percent of the 160,000 people who die of the dread disease every year.
DR. MICHAEL LEFEVRE: But a small proportion of a big number is still a big number. And 20,000 lives is a lot of people.
KNOX: Nearly 90 million Americans are smokers or former smokers. The task force is targeting 7 million of them for annual CAT scans. They're people between 55 and 79 who've smoked the equivalent of a pack of cigarettes a day for 30 years. If they've quit, it needs to have been within the past 15 years to qualify. The task force gives lung cancer screening a grade of B. That puts it on par with mammography in terms of effectiveness. In fact, LeFevre says it's better.
LEFEVRE: We can, in fact, screen fewer people and avoid more deaths than we can with mammography.
KNOX: It takes 320 lung scans of high-risk people to prevent one lung cancer death. But it takes 900 scans of women past 50 to prevent one death from breast cancer. By law, a task force grade of A or B obligates Medicare and private insurers to cover a screening test with no cost to consumers. Besides mammography, there are only two other approved cancer screening tests: colonoscopy and pap smears. Both of those have an A rating.
But LeFevre cautions that lung cancer is by far the most complicated screening problem. A single scan can't distinguish between something that's cancer and something that's not. It takes repeated scans and sometimes biopsies.
LEFEVRE: Most abnormalities that are found on CT scan are not cancer, but they do lead to further testing, more radiation exposure, unnecessary anxiety for people worried about having cancer and even risky surgery. We are actually going to do some lung surgery on people just to prove that they don't have cancer.
KNOX: LeFevre says people who have an abnormal lung scan are going to have to be calm, patient and deliberate.
LEFEVRE: This is an anxiety that I have about lung cancer screening. If somebody hears they have a 5 percent chance that this is cancer, and then you say, well, let's wait three months and repeat your CAT scan, if the emotional response is no, let's do something now, then we're going to do a lot of harm in the process of doing a little good.
KNOX: A lot of patients will get unnecessary lung biopsies and even surgery. Dr. Kenneth Lin of Georgetown University thinks the task force is putting too much faith in lung screening.
DR. KENNETH LIN: They rank it with those tests that your doctor, if they're a good doctor, is supposed to bug you about to get done. And I don't feel that this test necessarily meets that criteria. I don't necessarily feel that patients should be pressured into getting this test done. But I think that's what the B recommendation signifies: it ought to be more or less routine.
KNOX: But Tom Murphy, a 61-year-old Maryland man, is convinced that annual screening prevented him from dying of lung cancer as his father did. Murphy, who smoked for three decades, started getting yearly lung scans in 2005 as part of a study. Five years later, a scan showed a spot on his right lung was growing.
TOM MURPHY: Oh, absolutely that scan saved my life. This thing started at five millimeters in January of 2010. And at the point they took it out, it was 1.2 centimeters, you know, nine months later. So I'm very grateful, and I believe to this day that it saved my life.
KNOX: But Murphy still has to get a lung scan every few months to see if something else is brewing. So he's not out of the woods.
MURPHY: I'd like to think that I am. But, you know, when I go down there, you know, they have this thing called scanxiety when you're a cancer patient. Before you - every scan, you go get, you get a little anxious or a lot anxious before your scan. I still get a little anxious before each scan.
KNOX: But in between scans, Tom Murphy relishes the times he can play with his new granddaughter. Richard Knox, NPR News. Transcript provided by NPR, Copyright NPR.