Hard on the heels of successful breast cancer screening programs, CT screening for a host of ailments that afflict aging baby boomers could be poised for a huge surge in the U.S.

Insurers are resisting the idea and many physicians question the wisdom of using CT to look for potential health problems in asymptomatic individuals. But that hasn't stopped enterprising imagers from setting up clinics and charging hundreds of dollars to find out if their patients have calcium in their coronary arteries or tumors in their lungs.

The phenomenon made headlines Thursday. The Wall Street Journal, in its lead article, described a number of programs that provide CT scans for asymptomatic people to screen for potential ailments ranging from cancer to cardiovascular disease.

The U.S. Army, for example, will spend $1 million this year to provide preventive screening of 4000 soldiers, and hopes eventually to have all its troops undergo full-body scans, the newspaper said. Another convert is the union representing Los Angeles police officers, which negotiated a discounted $190 CT exam for healthy members. A 44-year-old commander went for one of the discounted scans on a lark, and a golf-ball-sized tumor was found on one of her kidneys. A biopsy revealed it was malignant.

Two types of screening are drawing most of the attention. Coronary calcium screening with electron beam CT or specially adapted spiral CT scanners is being aggressively advertised and promoted at imaging centers throughout the nation, although the value of calcium scores in predicting heart disease is far from a settled question.

The cover story of the April edition of Diagnostic Imaging takes a look at the marketing of coronary calcium screening and the controversy over its clinical utility. The story also covers the debate between advocates of electron beam CT, the pioneer in coronary calcium scans, and more recently introduced spiral CT calcium scoring packages.

"Marketing messages describe the benefits of coronary calcium screening with firm conviction. In fact, however, the clinical data are both complex and contradictory, and the wait for solid answers could take four years or more," writes medical editor Catherine Carrington.

A little further in the curve but still poised for strong growth is low-dose CT scanning for lung cancer. Favorable data that emerged last summer from the Early Lung Cancer Action Project (ELCAP) drew widespread media attention and prompted a surge of calls to hospitals and clinics from smokers and ex-smokers who wanted to be scanned to assure themselves that they don't have lung cancer.

The ELCAP protocol and the hot debate over lung cancer screening is the subject of the cover story in the May issue of Diagnostic Imaging.

"The early results have stirred debate about the value and limitations of the ELCAP protocol and the composition of future trials to fully examine its clinical efficacy," writes DI senior editor James Brice. "One side supports short-term studies in the hope that rapid results will save lives. The other urges long-term randomized trials, fearing that premature adoption could waste billions of dollars and subject many patients to unnecessary procedures."

While calcium and lung screening take center stage, some radiologists are looking at CT scans as part of a more general checkup.

Mayo researchers, for example, have developed a protocol for a 10-second, whole-body CT scan that checks for lung nodules, coronary artery calcification, bone density, and fat distribution, which can signal the risk for cardiovascular disease and diabetes.

"Although much more testing is needed, it appears that we can screen people in their street clothes for medical conditions responsible for the most common causes of death," said Dr. Stephen Swensen, director of radiology at the Mayo Clinic in Rochester, MN. Look for additional details on the scan protocol in the May DI.

And in Newport Beach, CA, radiologist Harvey Eisenberg offers a neck-to-pelvis EBCT scan that he says simultaneously screens for the very early detection of coronary heart disease, most types of cancer (including breast and lung cancer), emphysema, aneurysms, osteoporosis, ovarian and prostate disease, and several other diseases.

Eisenberg told The Wall Street Journal that his Health View Center for Preventative Medicine should draw more than 11,000 patients this year. Revenue for the center is now $3 million per year, but could go to $9 million as a result of leasing to other facilities the custom software for processing the scans, he said.

— By John C. Hayes