Study: CT Screening Cuts Lung Cancer Deaths

CT Scans May Be Better Screening Method Than X-Rays for People at High Risk of Lung Cancer

June 29, 2011 -- Screening smokers and former smokers for lung cancer with low-dose CT imaging saves lives, a huge, decade-long study shows, but experts say it is too soon to recommend screening for everyone at risk.

Heavy smokers and former smokers who had the CT imaging were 20% less likely to die of lung cancer than smokers who got traditional chest X-rays.

Results from the National Lung Screening Trial, which included more than 53,000 people, were reported Wednesday in the New England Journal of Medicine.

The study is the first to show that screening can reduce lung cancer mortality by finding tumors early. But many questions remain, including who should have the test and at what cost to the health care system.

"We now know that it is possible to reduce deaths from lung cancer with low-dose CT, and now we need to figure out what to do with this knowledge," Dartmouth Medical School professor of medicine Harold C. Sox, MD, tells WebMD. "There are about 94 million smokers or former smokers in the United States, and screening even a portion of them would be very expensive."

Lung cancer claims about 157,000 lives a year in the U.S., according to the National Cancer Institute, which sponsored the study together with the American College of Radiology Imaging Network.

Beginning in the summer of 2002, more than 53,000 heavy smokers and former heavy smokers between the ages of 55 and 74 were enrolled in the study at 33 sites across the country.

The participants were randomly assigned to receive three annual screenings with either low-dose spiral CT or standard chest X-ray.

A traditional X-ray produces a single image of the chest, while spiral CT involves multiple, three-dimensional images of the chest cavity.

Studies show standard X-ray screening to be somewhat effective for identifying lung cancers, but it has never been shown to reduce deaths from the disease.

During the screening phase of the trial, 39% of the low-dose CT participants and 16% of the standard X-ray group had at least one positive screening result; more than nine out of 10 positive tests in the first round of screening led to further diagnostic testing.

Many in U.S. Skip Follow-up Colon Cancer Screening

Survey Shows About One-Third of Americans Aren't Following Guidelines for Repeat Screenings

June 24, 2011 -- One in three adults who have been screened for colon cancer fail to follow up with repeat screenings as recommended, according to a new survey.

Researchers found 33% of U.S. adults between the ages of 60 and 70 years old have only been screened once for colon cancer; 31% of adults over age 50 have never been screened at all.

"The survey suggests that people are not being screened at a rate of frequency that reflects adherence to medical guidelines for colon cancer testing," says Andrew Spiegel, CEO of the Colon Cancer Alliance, which co-sponsored the survey with Quest Diagnostics, in a news release. "It is possible that many patients, after being screened once, are lulled into a false sense of security and fail to undergo additional testing."

Colon cancer is the second leading cause of cancer deaths in the U.S. The CDC says 60% of colon cancer deaths could be prevented if people followed guidelines for regular screening.

The American Cancer Society guidelines recommend men and women at average risk for colon cancer begin colon cancer screening at age 50 and repeat screening on a regular basis. Some of the types of recommended screening tests available, and their frequency, include:

Colonoscopy: every 10 yearsFlexible sigmoidoscopy or virtual colonoscopy: every five yearsFecal occult blood (FOBT) and fecal immunochemical (FIT) tests: annually

The telephone survey of 1,304 adults suggests that gaps in colon cancer screening persist despite public education campaigns.

The results show nearly one in three adults over age 50 have never been screened for colon cancer by any method. More than a quarter (28%) of these said their health care provider did not recommend colon cancer screening to them.

Other frequently cited reasons for not undergoing colon cancer screening include:

Time constraints or being "too busy": 18%Fear: 16%Didn't know screening was necessary: 16%Can't afford health insurance co-payment: 15%No health insurance: 10%Modesty or embarrassment: 9%

Among those who had been screened, 87% said they had been screened by colonoscopy, which is the preferred screening method. But researchers say fears about unpleasant bowel preparation (laxatives and fasting) were cited by 61% of those who said fear was a reason they had never been screened for colon cancer.

Among adults over age 50 who said they had been screened in the past:

40% had been screened once22% had been screened twice12% had been screened three times18% had been screened four or more times by any colon cancer screening method

The survey also looked at how people who were aware of colon cancer screening guidelines had learned about them. Eighty percent said their health care provider had told them about the guidelines. Other sources included friends (23%) and family (31%). The Internet was the source of information for 12% of the respondents.

"Clearly, family and friends as well as health care providers can influence public understanding of the value of colon cancer testing," Spiegel says.

Researchers said the survey also suggests that health care providers have the opportunity to educate their patients about the variety of screening options available for colon cancer and their recommended frequency.