CT scan may help on lung cancer

WASHINGTON

Screening smokers and ex-smokers with high-tech CT scans has been shown for the first time to significantly reduce deaths from lung cancer, federal health officials said yesterday, citing a major national study involving Wake Forest University Baptist Medical Center and other research sites.

The long-awaited study of more than 53,000 middle-aged and elderly people who either once smoked or currently smoke heavily found there were 20 percent fewer deaths among those who underwent an annual special CT scan compared with those who got standard chest X-rays.

The findings on the spiral CT scans were so striking that the National Cancer Institute, which sponsored the study, stopped the National Lung Screening Trial early so the public and participants could be alerted.

“This finding has important implications for public health with the potential to save many lives among those at greatest risk for lung cancer,” said Harold Varmus, the director of the cancer institute. “This finding will be an important factor in subsequent efforts to protect the tens of millions of former and current smokers in this country against the lethality of lung cancer.”

The $250 million study, which started in 2002, involved men and women at 33 sites across the country.

Wake Forest Baptist enrolled 1,155 of the participants in the study. Dr. Caroline Chiles, a radiologist, was the principal investigator at the medical center.

Lung cancer strikes more than 196,000 Americans each year and kills more than 159,000 — more than breast, colorectal, pancreatic and prostate cancers combined.

Although advances have been made in reducing deaths from other leading cancers, lung cancer has remained resistent and most victims die.

The new finding marks the first good news about the disease in decades. There are an estimated 91.5 million current and former smokers in the United States, all of whom are at increased risk for lung cancer.

CT scans, which create a three-dimensional image of the lungs instead of a one-dimensional perspective captured by standard chest X-rays, can spot more tumors when they are smaller and can be more successfully removed through surgery, boosting the chances of survival.

The findings were hailed by the American Cancer Society, American Lung Association, and others.

“With this positive trial result we have the opportunity to realize the greatest single reduction of cancer mortality in the history of the war on cancer,” said James Mulshine, of Rush University Medical Center, in a statement issued by the Lung Cancer Alliance.

Even though CT scans can be performed by most hospitals, experts stressed that it was too soon to issue any specific recommendations about the use of CT screening for lung cancer.

More analysis is needed to identify exactly who might benefit and how often they should be screened, they said.

Some expressed concern that the findings may lead to too many people undergoing unnecessary screening.

The scans found abnormalities in about 25 percent of those screened, but most turned out to be a false alarm.

“Will the public health community be able to manage the immediate consequences of this result, and ensure that there is a carefully planned rollout of screening to those individuals who will likely benefit, and with screening offered in places where follow-up care is available?” Peter Bach, of Memorial Sloan-Kettering Cancer Center in New York wrote in an e-mail. “Or will we see an avalanche of entrepreneurial radiologists taking out full-page ads and billboards tomorrow overstating the magnitude of the benefit, and without any plan in place for how to handle whatever is found or how to select the right patients for screening?”

Previous studies had produced mixed results about the usefulness of the screening to try to catch lung cancer in its earliest, more treatable stages.

It remained unclear whether the benefits outweighed the risks from radiation from the low-dose scans and the dangers, stress and anxiety from unnecessary biopsies and other treatment caused by false alarms.

Experts stressed that smoking was the leading cause of lung cancer and the best way to fight the disease was to either never smoke or stop smoking.

“These findings should in no way distract us from continued efforts to curtail the use of tobacco, which will remain the major causative factor for lung cancer and several other diseases,” Varmus said.

Widescale CT screening, which costs about $300 for each exam, could be extremely costly.

Currently, Medicare and most private health insurers do not cover CT scans for lung-cancer screening.

But officials at the Centers for Medicare & Medicaid Services said they would review the new findings.

Participants in the study had to have smoked at a pack a day for 30 years. They also had to have no signs or history of lung cancer.

Participants were randomly assigned to receive three annual screenings with either the CT scans or a standard chest X-ray.

The subjects were then followed for up to another five years to see who developed lung cancer. Those who received a diagnosis received standard treatment.

A total of 354 deaths from lung cancer occurred among the subjects who underwent CT scans, compared with 442 among those who got the chest X-rays — a 20.3 percent reduction in lung-cancer mortality.