Every year, lung cancer kills more Americans than colon, breast and prostate cancers combined.
So the news last year of a national trial showing that high-tech CT scans for early detection could improve survival was widely hailed. But Medicare and private insurance aren't covering it yet, and the American Cancer Society still hasn't endorsed the practice.
Even so, some health care providers are offering the test for those who'll pay up to a few hundred dollars cash. And Tampa's Moffitt Cancer Center announced that it is offering the test to those at high risk of lung cancer.
"We don't want to wait for Medicare and other insurance plans to cover it before we offer this screening," said Dr. Jacques-Pierre Fontaine, a thoracic oncologist at Moffitt. "It's much cheaper to the health care system to treat an early cancer than it is to treat a late stage, advanced cancer."
The trouble, as even advocates like Fontaine say, is that CT scans detect all kinds of irregularities that are not cancer, especially in smokers who are prone to lung cysts and scarring. So patients may face unnecessary medical tests and surgical procedures that could themselves be harmful.
"It takes an experienced lung cancer specialist to know which (lesions) require further testing, which ones need to be rescanned in three months, and which ones you can tell patients, 'Don't worry, this doesn't look like cancer,"' Fontaine said.
In an email, the American Cancer Society's chief medical officer, Dr. Otis Brawley, called the national trial momentous. Still, he said, anyone considering screening should be aware of the potential for false positives and the risks associated with diagnostic testing.
Announced in November, the National Lung Screening Trial, or NLST, was the first to prove that a lung cancer-screening test could save lives.
Lung cancer is so deadly because by the time symptoms are felt, it often is too late for successful treatment. The NLST found that low-dose CT scans pick up lung cancers when they are small, about the size of a pea. What's more, the testing improved survival by 20 percent, compared to standard chest X-rays.
Retired Pinellas-Pasco (Fla.) Circuit Court Judge Susan Schaeffer was a participant in the trial. A longtime smoker, she saw a Moffitt advertisement for NLST study participants and signed up. For three years, she got a clean bill of health. But the fourth-year scan, in 2004, revealed cancer.
The tumor was found early, before she had symptoms. She gave up cigarettes, went through chemotherapy and radiation, and is considered cancer-free today.
"If not for that test, I'd be dead," said Schaeffer, 69, who plays golf three times a week.
Researchers used what is known as low-dose helical (or spiral) CT scanning. The patient lies on a table that slides into a large, doughnut-shaped machine. A tube in the round scanner emits radiation to produce a series of cross-section images of body tissue and organs, much like slices of bread.
Radiation exposure is estimated at 20 percent of that from a conventional CT scan, according to Dr. Denise Aberle, a UCLA radiologist and a principal investigator in the trial. The dose has been described as equal to less than a year's worth of natural radiation exposure from the environment.
Specialists are scrambling to establish guidelines for the scans. Among the issues: who should be screened, how often, and who needs more testing, such as a surgical biopsy.
"We are working to fast-track new guidelines that will factor in the new research," said Dr. W. Michael Alberts, chief medical officer at Moffitt and chairman of the American College of Chest Physicians committee working on the guidelines.
Nobody is suggesting that low-dose CT scans should be used as widely for cancer screening as, say, mammograms. Rather, experts say they're most appropriate for older people who are or have been long-term smokers, or for people with a family history of lung cancer.
Do you need a scan? Until national guidelines are in place, the American Cancer Society advises talking with your doctor about screening if you think you're at high risk.
(Contact Irene Maher at firstname.lastname@example.org.