ORIGINAL ARTICLE Can the synthetic C view images be used in isolation for diagnosing breast malignancy without reviewing the entire digital breast tomosynthesis data set? Mark C. Murphy 1 & Louise Coffey 1 & Ailbhe C. O’Neill 1 & Cecily Quinn 1 & Ruth Prichard 1 & Sorcha McNally 1 Received: 16 October 2017 /Accepted: 17 January 2018 # Royal Academy of Medicine in Ireland 2018 Abstract Aims and objectives The aim of this study was to determine if the synthetic C view acquired at digital breast tomosynthesis (DBT) would give adequate information to confirm a malignancy and could obviate the need to review all the tomosynthesis image data set. Methods All patients with biopsy-proven breast cancer recalled from screening mammograms between May and September 2016 were included for review. For each patient, the screening 2D mammogram, the synthetic C view, and the DBT images were reviewed by three breast radiologists and each assigned a BIRADS code. Any discrepancies were reviewed and resolved by consensus. Results A total of 92 patients were diagnosed with breast cancer in this time period. Fourteen were excluded because they did not have DBT performed. Five women were recalled for evaluation of two lesions. In total, 83 lesions were assessed. In 27 cases, the BIRADS code remained unchanged in the three modalities. In 16 cases, the lesions appeared more concerning on C view and DBT that on the original mammogram but were not definitive for malignancy (BIRADS 4). In 29 cases, a BIRADS 5 code was assigned on C view and tomosynthesis but not on 2D. For 11 lesions, a BIRADS 5 code was assigned only on DBT. Four women had BIRADS 5 lesions seen on both the C view and DBT that were not seen on the screening 2D mammogram. One was multifocal. Conclusion While the synthetic C view gives additional information when compared to a screening 2D mammogram, the full DBT tomosynthesis data set needs to be reviewed to diagnose a breast malignancy. Keywords Breast cancer . Mammography . Synthetic view . Tomosynthesis Aims and objectives Population-based screening with full-field digital mammogra- phy (FFDM) is widely used in the detection of asymptomatic breast cancer. Research suggests that screening offers a rela- tive reduction in mortality from breast cancer of approximate- ly 20% [1, 2]. FFDM is a 2D image, and while a very effective screening tool, it is not without limitations. Superimposed glandular tissue can obscure tumors within the breast and cancers which can be missed in up to 15–30% of cases [3]. The sensitivity of FFDM is lower in women with dense breast tissue. Recall to assessment is increased in women with dense breast tissue because of tissue overlap [4]. The development of digital breast tomosynthesis (DBT) appears to have increased sensitivity [5]. This is a relatively new tomographic technique in mammography. Tomographic images of the breast are reconstructed from multiple low-dose projection images that are acquired by moving the X-ray tube in an arc over a limited angular range. This effectively creates a 3D image of the breast. In allowing the reporter to scroll through multiple images, the confounding effect of overlying glandular tissue is removed and cancer detection rates are improved [5]. There is also a reduction in false positives, as images that may appear sus- picious on FFDM can be better evaluated [5]. In 2011, the FDA approved the use of DBT as an adjunct to FFDM. They specified however that all DBT images must be interpreted in conjunction with the FFDM images. It has been shown that the use of mammography plus DBT combined in a screening environment resulted in a significantly higher * Mark C. Murphy mark.murphy@ucdconnect.ie 1 National Breast Screening Programme, Merrion Unit, St Vincent’ s University Hospital, Dublin 4, Ireland Irish Journal of Medical Science (1971 -) https://doi.org/10.1007/s11845-018-1748-7