Comparative Benefit-to-Radiation Risk Ratio of Molecular Breast Imaging, Two-Dimensional Full-Field Digital Mammography with and without Tomosynthesis, and Synthetic Mammography with Tomosynthesis.

PURPOSE: To apply previously published benefit-to-risk ratio methods for mammography and molecular breast imaging (MBI) risk estimates to an expanded range of mammographic screening techniques, compressed breast thicknesses, and screening views.

MATERIALS AND

METHODS

Only previously published estimates were used; therefore, this study was exempt from the requirement to obtain institutional review board approval. Benefit-to-risk ratios were calculated as the ratio of breast cancer deaths averted and lives lost to screening over 10-year intervals starting at age 40 years for MBI, two-dimensional (2D) full-field digital mammography (FFDM) alone, 2D FFDM with synthetic mammography, and 2D FFDM with tomosynthesis for two-, four-, and five-view screening mammography and compressed breast thicknesses of 20-29 mm, 50-59 mm, and 80-89 mm.

RESULTS

Central estimates of the benefit-to-risk ratios ranged from 3 to 179 for screening mammography and from 5 to 9 for MBI. Benefit-to-risk ratios for MBI were inferior to those for mammography for most scenarios, but MBI may be performed at an equal or superior benefit-to-risk ratio for women aged 40-59 years with a compressed breast thickness of at least 80 mm and for those undergoing mammographic screening examinations with four or five views per breast. The benefit-to-risk ratios across all ages with use of tomosynthesis plus 2D FFDM as a screening examination were 45% lower than those for tomosynthesis plus synthetic mammography.

CONCLUSION

Benefit-to-risk ratios for MBI are within the lower range of those for mammography when accounting for variation in mammography technique, compressed breast thickness, and age. Benefit-to-risk ratios of synthetic mammography plus tomosynthesis are superior to those of tomosynthesis plus 2D FFDM.Keywords: Breast, Mammography, Molecular Imaging, Molecular Imaging-Cancer, Radiation Safety, Radionuclide Studies, Screening, Tomosynthesis© RSNA, 2019See also the commentary by Hruska in this issue.