Objectives: To estimate detection measures for tomosynthesis and standard mammography; to assess the feasibility of using tomosynthesis in population-based screening for breast cancer.Design, setting: Prospective pilot trial comparing tomosynthesis (with synthesised 2D images) and standard mammography screening of women attending Maroondah BreastScreen, a BreastScreen Victoria service in the eastern suburbs of Melbourne.Participants: Women at least 40 years of age who presented for routine breast screening between 18 August 2017 and 8 November 2018. Main outcome measures:Cancer detection rate (CDR); proportion of screens that led to recall for further assessment.Results: 5018 tomosynthesis and 5166 standard mammography screens were undertaken in 10 146 women; 508 women (5.0% of screens) opted not to undergo tomosynthesis screening. With tomosynthesis, 49 cancers (40 invasive, 9 in situ) were detected (CDR, 9.8 [95% CI, 7.2-13] per 1000 screens); with standard mammography, 34 cancers (30 invasive, 4 in situ) were detected (CDR, 6.6 [95% CI, 4.6-9.2] per 1000 screens). The estimated difference in CDR was 3.2 more detections (95% CI, -0.32 to 6.8) per 1000 screens with tomosynthesis; the difference was greater for repeat screens and for women aged 60 years or more. The recall rate was greater for tomosynthesis (4.2%; 95% CI, 3.6-4.8%) than standard mammography (3.0%; 95% CI, 2.6-3.5%; estimated difference, 1.2%; 95% CI, 0.46-1.9%). The median screen reading time for tomosynthesis was 67 seconds (interquartile range [IQR] 46-105 seconds); for standard mammography, 16 seconds (IQR, 10-29 seconds). Conclusions:Breast cancer detection, recall for assessment, and screen reading time were each higher for tomosynthesis than for standard mammography. Our preliminary findings could form the basis of a large scale comparative evaluation of tomosynthesis and standard mammography for breast screening in Australia.Trial registration: Australian New Zealand Clinical Trials Registry, AC TRN12617000947303.The known: Overseas studies have found that digital breast tomosynthesis (3D mammography) can increase breast cancer detection rates and reduce the frequency of unnecessary recalls for assessment.The new: Our prospective pilot trial of population-based tomosynthesis screening in Maroondah BreastScreen found that more breast cancers were detected by tomosynthesis (9.8 [95% CI, 7.2-13] per 1000 screens) than by standard mammography (6.6 [95% CI, 4.6-9.2] per 1000 screens), but the recall rate was also higher (4.2% v 3.0%). The implications:Tomosynthesis breast screening is feasible if infrastructure and service preparation are adequate. Our findings could inform larger evaluations of tomosynthesis and standard mammography for breast screening in BreastScreen.

Missed cancers were statistically significantly lower in density and more often seen on only one of two views than detected cancers.

Core biopsy showing benign papillary lesion, even where radiology is also suggestive of a benign process, cannot exclude malignancy, and therefore surgical excision is required.

PMBC are commonly lobulated with homogeneous, isoechoic and normal posterior acoustic sonographic appearances but rarely have benign imaging features.

Two-thirds of small IBCs displayed marked conspicuity variation, similar to RS. Therefore, conspicuity variation does not discriminate between IBC and RS.