For smokers with the dark fear of lung cancer lurking behind every cough or chest pang, the offer sounds too good to pass up:
Spend about $200 on a relatively new test called a spiral CT scan and get a quick and painless image of their lungs that can detect a speck of cancer before it grows, allowing treatment much sooner than would have been possible before.
As Life Scan 2000 of Florida, a Clearwater imaging center that has scanned hundreds of people in the last six months, explains in a recent newspaper ad, it's "a high speed scan of the lungs that can identify cancerous tumors when they are small enough to be cured."
Sounds good. But scientists aren't sure it's true. Although conventional wisdom and experience with other cancers teach that catching the disease early is the key to beating it, evidence is lacking that early detection of lung cancer through CT screening or any other means really helps victims live longer.
"It definitely picks up cancers earlier. So do chest X-rays. But believe it or not, that's not enough," said Dr. Robert Clark, chief of radiology at the H. Lee Moffitt Cancer Center and Research Institute in Tampa.
"So it's possible, unfortunately, to pick up cancers early and still not change the outcome."
And the spiral CT scan, gaining popularity across the country, picks up a lot of things that aren't cancers, too. According to the National Cancer Institute, nodules that may or may not be cancer show up in 20 percent to 30 percent of people. The vast majority won't be cancer, but more tests or surgery to find out for sure can be difficult and sometimes dangerous. And insurance won't cover lung cancer screening because it's considered experimental.
That hasn't deterred thousands of current and former smokers from seeking the sometimes aggressively marketed scans for lung cancer, the leading cause of cancer death in the United States.
Gina Johnson, president of Life Scan 2000 of Florida, said about three-quarters of those her company has scanned are current or former smokers, and most are in their 40s and 50s. The cost is $195.
Patients are told to review the results with their physicians, and doctors have told her they appreciate getting the earliest possible warning, Johnson said. She predicts the screenings will become as accepted as mammograms.
"Every day we're reading about new procedures and new technology that can be used to defeat cancer," she said Wednesday. "And the best chance you have is to catch it early.
"I'm sorry if a physician is offended, but it's my life. Statistics describe a population, not an individual."
Some answers about the benefits of CT scanning may be forthcoming. Three cancer research centers, including Moffitt, are studying how well it finds small, early stage lung cancers.
Doctors and the public have long known that early detection of many cancers, including prostate, breast and colorectal cancers, drastically improves the chances of survival.
Screening for these cancers has become standard medical practice, and millions are spent persuading Americans to get checked. But not one organization, not the National Institutes of Health or even the American Cancer Society, recommends screening for lung cancer, because of the lack of evidence that it helps.
And unlike some other cancers, which are relatively slow growing, lung cancer is aggressive and may begin to spread even before lesions can be detected.
Dr. Barnett Kramer, senior medical scientist at the National Cancer Institute, explains it like this: Imagine being chained to the railroad tracks in a long, flat desert. If you're given a device -- a pair of binoculars, for instance -- that allows you to see the train coming from farther away, you will detect the danger sooner. But the end remains the same.
Many researchers believe lung cancer may be like that.
In the 1970s, when using chest X-rays to screen for lung cancer became fashionable, four studies of men who smoked showed that those whose cancer was detected earlier died at the same rate as those whose cancer was detected later. A recent study at the Duke University Medical Center suggested the same thing, Kramer said.
Doctors desperately want help battling lung cancer, which kills 160,000 men and women a year.
Early stages have no symptoms, and it usually isn't detected until it has spread. It also is hard to treat. The one-year survival rate has increased only from 34 percent in 1975 to 41 percent in 1995, and 86 percent of patients are dead in five years. Nine of 10 smoked.
For Robert Ball, a retired submariner who lives in Tampa, numbers like that and two packs a day for 48 years were enough to make him join the Moffitt study.
"That's the whole idea as I perceive it, is to have the earliest possible findings so the patient would be much better off," said the retired lieutenant commander.
His spiral CT scans have revealed a number of hard, grainy items in his lungs. So far they've been benign, but he returns to Moffitt in a couple weeks so doctors can check some others.
"I think they're going to be history," he said. "I'm confident. But I'm comforted that they're going to keep looking."
The renewed interest in screening for lung cancer stems from a widely reported study last summer in The Lancet, a British medical journal, saying spiral CT scans could increase the five-year survival rate to nearly 80 percent.
Meanwhile, Clark said he expects more and more companies to offer CT scans for lung cancer, but he would prefer they don't blossom until the government can hold a large-scale trial.
"If people want it, and they're willing to pay cash for it, okay . . . as long as they're fully informed that it's unproven," Clark said.
But imaging centers might exploit people's fears, he added.
"People who are smokers or former smokers, there's a lot of them," Clark said. "So there's a tremendous opportunity for an awful lot of money to be spent by those people that maybe could be used for better things."
But Johnson of Life Scan said people deserve to know as much about their bodies as they can.
"We tell people all day long that this does not mean you do or do not have cancer," she said. "It means that at this point in time, this is what the CT image of your lung looks like." Smokers wanted.
