Abstract OT3-03-01: Diagnostic value of Three-dimensional UltRasound in women recalled from Dutch breast cancer screening with a BI-RADS 0 mammography result: The TURB0 study
Authors: den Dekker Bianca M , Broeders Mireille JM , Verkooijen Helena M , Venmans Alexander , Meeuwis Carla , Setz-Pels Wikke , Pijnappel Ruud M 
Published: March 2020

Abstract
Background: Three-dimensional automated whole-breast ultrasound (3D ABUS) is an emerging imaging technique that enables the standardized acquisition of volumetric images of the whole breast. Although more data become available on the added value of 3D ABUS both in the screening and diagnostic setting, to date this technique is not widely used in the Netherlands.
In the Netherlands, women between the ages of 50 and 75 years are invited for breast cancer screening every two years using full-field digital mammography. Approximately 2.4% of screening participants is recalled and referred to a hospital for diagnostic work-up of inconclusive (BI-RADS 0) or suspicious findings (BI-RADS 4/5). While over half of recalls from screening results from a BI-RADS 0 screening mammography, only 11% of these women has breast cancer. However, invasive diagnostic procedures are performed in every one in five women with a false-positive BI-RADS 0 recall. False-positive screening mammography results cause anxiety in the patient, especially when a biopsy is necessary. Furthermore, the diagnostic work-up after referral is costly and exerts pressure on health care facilities.
3D ABUS may be of added diagnostic value in women recalled from screening with a BI-RADS 0 mammography result. 3D ABUS may potentially lower the number of benign biopsies in the diagnostic setting and, in a future perspective, decrease the false-positive recall rate when used as an adjunct screening tool in women with a BI-RADS 0 screening mammography result. Therefore, we aim to investigate the diagnostic accuracy and added value of 3D ABUS in women recalled from Dutch breast cancer screening with a BI-RADS 0 mammography result.
Trial design: Observational multicenter prospective cohort study. The study was approved by the Medical Research Ethical Committee of the University Medical Center Utrecht. Written informed consent is obtained from all participants. In addition to screening mammography, tomosynthesis and hand-held ultrasound, bilateral, supine 3D ABUS imaging is obtained. Different imaging strategies are compared to determine the optimal combination of imaging modalities and the added value of 3D ABUS.
Eligibility criteria: Women recalled from Dutch breast cancer screening with a BI-RADS 0 screening mammography result and able to give informed consent are considered eligible.
Aim: To investigate the diagnostic accuracy and added value of 3D ABUS in women recalled from Dutch breast cancer screening with a BI-RADS 0 mammography result.
Statistical methods: Sensitivity, specificity, negative predictive value and positive predictive value of 3D ABUS will be calculated with 95% confidence intervals, using histopathology (if available) or follow up to the next screening round approximately two years later as the reference standard. The diagnostic accuracy of different imaging strategies in the diagnostic work-up will be compared with pairwise McNemar tests and area under the receiver operating characteristic curve analyses. A p-value &lt;0.05 will be considered statistically significant. Screening mammography will be assessed in combination with 3D ABUS imaging to calculate the number of false-positive BI-RADS 0 recalls that 3D ABUS may prevent. Subgroup analysis will be performed based on four breast density categories, measured with automated breast density software, to evaluate the added value of 3D ABUS specifically in women with dense breasts.
Present accrual: 360 (April 2018 - June 2019). Target accrual: 600 (expected in April 2020)
Acknowledgements: The TURB0 study is funded by General Electric. Hologic provided the breast density assessment software for the purpose of this study.
Contact information: B.M.denDekker-3@umcutrecht.nl
Citation Format: Bianca M den Dekker, Mireille JM Broeders, Helena M Verkooijen, Alexander Venmans, Carla Meeuwis, Wikke Setz-Pels, Ruud M Pijnappel. Diagnostic value of Three-dimensional UltRasound in women recalled from Dutch breast cancer screening with a BI-RADS 0 mammography result: The TURB0 study [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr OT3-03-01.