There is now solid scientific evidence, derived from several randomized controlled trials, of a statistically significant breast cancer mortality reduction for women age 40 and older who undergo routine screening mammography.<sup>2Andersson I., Janzon L. Reduced breast cancer mortality in women under age 50: Updated results from the Malmö mammographic screening program Monogr Natl Cancer Inst 1997 ;  22 : 63 [cross-ref]

Cliccare qui per andare alla sezione Riferimenti, 6Bjurstam N., Björneld L., Duffy S.W., e al. The Gothenburg breast screening trial: First results on mortality, incidence, and mode of detection for women ages 39–49 years at randomization Cancer 1997 ;  80 : 2091 [cross-ref]

Cliccare qui per andare alla sezione Riferimenti, 21Hendrick R.E., Smith R.A., Rutledge J.H., e al. Benefit of screening mammography in women aged 40–49: A new meta-analysis of randomized controlled trials Monogr Natl Cancer Inst 1997 ;  22 : 87

Cliccare qui per andare alla sezione Riferimenti</sup> Because of the convincing nature of this evidence, the remaining controversy about the widespread use of screening has, for the most part, shifted to concerns about the risks (harms) of mammography, concentrating on the morbidity and economic costs of false-positive cases.<sup>3Beam C.A., Layde P.M., Sullivan D.C. Variability in the interpretation of screening mammograms by US radiologists: Findings from a national sample Arch Intern Med 1996 ;  156 : 209

Cliccare qui per andare alla sezione Riferimenti, 13Elmore J.G., Barton M.B., Moceri V.M., e al. Ten-year risk of false positive screening mammograms and clinical breast examinations N Engl J Med 1998 ;  338 : 1089 [cross-ref]

Cliccare qui per andare alla sezione Riferimenti, 14Elmore J.G., Wells C.K., Lee C.H., e al. Variability in radiologist's interpretations of mammograms N Engl J Med 1994 ;  331 : 1493 [cross-ref]

Cliccare qui per andare alla sezione Riferimenti</sup> It is beyond the scope of this article to join in the debate. Rather, the aim herein is to discuss several already demonstrated methods that permit radiologists safely and effectively to reduce the frequency of false-positive mammography interpretations. In my opinion, the widespread implementation of these successful methods currently represents the best argument in defense of mammography that can be advanced by the radiology community.

One must remember that the primary goal of mammography is to detect nonpalpable, favorable-prognosis cancer; it is not to have relatively few false-positive cases. As a first priority, the radiologist should strive to achieve a high cancer detection rate, with the great majority of cancers being nonpalpable and early in stage. Only once such a level of success is demonstrated should one attempt to reduce the rate of false-positive interpretations. In other words, first establish the benefit and then attempt to minimize the harms (while maintaining an acceptable level of benefit). Because any strategy designed to reduce the frequency of false-positive cases requires examinations otherwise interpreted as positive to instead be read as negative, and because this leads to a reduction in the number of true-positive cases if any cancers are thereby overlooked, it is clear that successful approaches to reducing false-positive interpretations achieve this goal only if there is no more than a minor decrease in the early detection of favorable-prognosis cancers. Any initially overlooked cancers should still be of good prognosis when ultimately detected, demonstrating favorable clinical outcomes after treatment.