Breast tomosynthesis and digital mammography: a comparison of diagnostic accuracy

Epidemiology of Breast Cancer - Current Figures and Trends

The epidemiology of breast cancer has clearly changed in the past few years. On the basis of current data from population-based cancer registries characteristic numbers for incidence, prevalence, mortality and survival after breast cancer are presented. The number of incident cases has increased to around 72 000 in 2009 (+ 23 % since 2003). It is estimated that at present 250 000 women with a prevalent breast cancer (5-year prevalence) are living in Germany. The most frequent localisation is the outer upper quadrant of the breast. Poorly differentiated or undifferentiated tumour tissue is found in every third patient. Since 2003 the age-standardised mortality has declined slightly (- 9 %) whereas the relative survival has improved from 79 to 86 %. Changes in the epidemiology of breast cancer can most probably be attributed to the introduction of early detection programmes such as mammography screening as well as to improved treatment options. To what extent mammography screening will lead to a further reduction of mortality remains to be seen.

Digital tomosynthesis: a new future for breast imaging?

The aim of this article is to review the major limitations in current mammography and to describe how these may be addressed by digital breast tomosynthesis (DBT). DBT is a novel imaging technology in which an x-ray fan beam sweeps in an arc across the breast, producing tomographic images and enabling the production of volumetric, three-dimensional (3D) data. It can reduce tissue overlap encountered in conventional two-dimensional (2D) mammography, and thus has the potential to improve detection of breast cancer, reduce the suspicious presentations of normal tissues, and facilitate accurate differentiation of lesion types. This paper reviews the latest studies of this new technology. Issues including diagnostic efficacy, reading time, radiation dose, and level of compression; cost and new innovations are considered.

Mammographic screening for breast cancer: A review

In 2011, BreastScreen Australia celebrated 20 years of mammographic screening for breast cancer in Australia. There has been a reduction in mortality from breast cancer over the last two decades, coincident with mammographic screening. However, there are concerns that mammographic screening may result in overdiagnosis of breast cancer and that the reduction in mortality from breast cancer is the result of better treatment rather than screening. This article reviews the evidence on which mammographic screening for breast cancer is based, considers the issue of overdiagnosis of breast cancer by screening mammography, and assesses the role of screening mammography in the reduction in breast cancer mortality seen over the last two decades.

Performance comparison of single-view digital breast tomosynthesis plus single-view digital mammography with two-view digital mammography

OBJECTIVE

To determine the performance of combined single-view mediolateral oblique (MLO) digital breast tomosynthesis (DBT) plus single-view cranio-caudal (CC) mammography (MX) compared with that of standard two-view digital mammography.

METHODS

A multi-reader multi-case (MRMC) receiver-operating characteristic (ROC) study was conducted, involving six breast radiologists. Two hundred fifty patients underwent bilateral MX and DBT imaging. MX and DBT images with the adjunct of the CC-MX view from 469 breasts were evaluated and rated independently by six readers. Differences in mean areas under the ROC curves (AUCs), mean sensitivity and mean specificity were analysed by analysis of variance (ANOVA) to assess clinical performance.

RESULTS

The combined technique was found to be non-inferior to standard two-view mammography (MX((CC+MLO))) in mean AUC (difference: +0.021;95 % LCL = -0.011), but was not statistically significant for superiority (P = 0.197). The combined technique had equivalent sensitivity to standard mammography (76.2 % vs. 72.8 %, P = 0.269) and equivalent specificity (84.9 % vs. 83.0 %, P = 0.130). Specificity for benign lesions was significantly higher with the combination of techniques versus mammography (45.6 % vs. 36.8 %, P = 0.002).

CONCLUSION

In this enriched study population, the combination of single-view MLO tomosynthesis plus single-view CC mammography was non-inferior to that of standard two-view digital mammography in terms of ROC curve area, sensitivity and specificity.