screening holds the greatest potential to realize the benefits of reducing the incidence rate of advanced cancers.
Harmon J. Eyre, Robert A. Smith, Curtis J. Mettlin
Cancer Screening and Early Detection, 2003
State and federal legislators have taken an active role in exploring ways to improve breast cancer detection. The federal Mammography Quality Standards Act represents an unusual governmental intervention aimed at, and successful in, improving the technical quality of mammography. In the future, the MQSA may address the vexing problem of variation in radiologist interpretation of breast images. In spite of the impression left by widespread coverage in the national media,f differences among radiologists are not the largest component of the problem of inconsistency in interpretation. Other factors, notably organizational factors, have received much less attention, and are more difficult to control than individual factors, such as volume or training requirements.
New technologies, such as digital mammography, CAD, and MRI are being examined. Although they have advantages in some situations that may justify their use, they can add significant costs, and their value as improvements in sensitivity and specificity over screen-film mammography has not been established.
Organizational factors such as double reading by two radiologists improves accuracy; high volume centers on average have higher accuracy, above and beyond the increase attributable to reading volume of individual radiologists; and use of CAD can reduce the variability in mammographic interpretation among different readers.
As the U.S. population ages, demand for mammography will rise at a time when supply of personnel and facilities appears to be falling, increasingly threatening access. Among other things, low reimbursement and the unattractiveness of breast imaging as a subspecialty due to stress and malpractice litigation seem to be driving the impending shortages. Other problems include a dearth of radiologist researchers to conduct trials and investigate new approaches to breast cancer detection. To address the shortage of mammographers, expansion of responsibilities by nonphysicians to include preliminary interpretation of images should be considered. A key to improving mammographic interpretation is to reduce known and controllable sources of variability in quality, but at the same time to avoid adding to the burden of an already overextended workforce.