Current evidence for the use of emerging radiologic technologies for disease screening.

Recent technologic advances in the field of radiology have resulted in the availability of several new tests with potential applications for disease screening. Presently, these tests are being marketed directly to patients as noninvasive means to provide peace of mind that they are disease free. Such assurance is appealing to many individuals, and some are willing to spend up to 1500 dollars to choose from a menu of available diagnostic options. Given that a physician's referral is unnecessary, many healthcare providers are unaware that such testing has taken place until their patients present to them with abnormal test results. In this review, we examine the evidence supporting the use of electron beam computed tomography for coronary artery disease screening, spiral computed tomography of the chest for lung cancer screening, computed tomographic colonography for colon cancer screening, and total-body computed tomography for general screening. Although some of these modalities show promise for the future, there is insufficient evidence to support the use of any of these testing methods for secondary prevention. The potential for harm associated with false-positive test results, false-negative test results, undue anxiety, and radiation exposure exists but requires further study to quantify actual risk.