Digital mammography in breast cancer screening: A step forward?

摘要

Screening can be defined as the application of a relatively simple test to identify early, asymptomatic disease. The primary aim of cancer screening is to reduce mortality from this disease. This is possible if cancers detected and treated at an early stage are associated with better survival than those detected symptomatically. From the literature, there is convincing evidence that early detection of cancer contributes significantly to public health and has a profound impact on health care. As such, screening is a key instrument in the fight against cancer. In breast cancer screening, we distinguish between opportunistic screening and population-based breast cancer screening programs. The latter have a high level of central organization and a quality assurance scheme that target a specific age group. In this editorial, we only discuss population-based programs, also referred to as 'service screening'.Recently, in most of these programs in western Europe and in the USA, we have seen a gradual implementation of digital mammography as the primary screening method. Mammography makes use of low energy x-ray transmission to produce high contrast projection images in soft tissues. Contrast resolution is improved by digital mammography at the slight expense of spatial resolution. Furthermore, the raw data of digital images can be manipulated with dedicated display algorithms enhancing the ability to detect subtle structures, such as microcalcifications and small densities. Digital mammography has been accepted as a valuable successor to conventional screen-film mammography. An important step towards the implementation of digital mammography was the outcome of the Digital Mammographic Imaging Screening Trial (DMIST), carried out in the USA and published in 2005. The results showed that digital mammography was at least as good as screen-film mammography and even better in dense breasts, in younger and premenopausal women. In The Netherlands, implementation of digital screening mammography was preceded by pilot studies. The complete roll-out of a fully digital mammographic service screening program started in 2009 and was completed in 2010.