The Digital Breast Tomosynthesis Trial in Bergen (TOBE)
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ClinicalTrials.gov Identifier: NCT02835625 |
Recruitment Status :
Completed
First Posted : July 18, 2016
Results First Posted : January 15, 2021
Last Update Posted : July 30, 2021
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Breast Neoplasms | Radiation: Synthetic Mammography + Digital Breast Tomosynthesis Radiation: Digital mammography | Not Applicable |
DBT is a new screening tool, argued to be better than standard DM. This statement is based on a lower recall rate, and a higher rate of early-stage screen-detected cancer. No studies have so far reported results from women screened with DBT from GE Healthcare, as far as the investigators know. DBT from GE offer synthetic two-dimensional DM generated from the DBT data (SM), and studies have shown similar detection rates for this technique as of adjacent DM. By comparing results of early performance measures and economic aspects in two comparable populations of women in the same age group, residing in the same county, the investigators can measure the effect of SM+DBT versus standard DM with equipment from GE Healthcare. The populations will be examined by the same radiographers, screen-read by the same radiologists, histologically breast cancer proven by the same pathologists, and treated by the same surgeons and oncologists.
A prospective cohort study targeting 45,000 women invited to breast cancer screening in Bergen, Hordaland in the study period, 2016-2018, will be performed. A screening participation of approximately 75% is expected. All attending women will be asked if they are willing to participate in the study after receiving written and oral information about the study. Women willing to participate in the study will sign an informed consent. Of the attending women it is expected that about 90-95% will consent to participate in the study. The women will be randomized into two groups, a study group and a control group. The randomization will take place at the screening unit in Bergen. The outcome of the randomization is based on the 11-digit personal identification number assigned to every citizen in Norway. In the study group, the women will be screened with SM+DBT. In the control group, the women will be screened with DM. Women not willing to participate in the study will be screened with DM, and not included in our study.
The investigators aim to address the following topics and research questions:
- Study 1: Early performance measures in a population based screening program using SM+DBT versus DM - interim analyses.
- Study 2: Use of SM+DBT versus DM in a population based screening program - a randomized controlled trial.
- Study 3: Prognostic and predictive histopathologic characteristics of breast tumors detected in a population based program using SM+DBT versus DM.
- Study 4: SM+DBT and DM in a populations based screening program - which technology has the highest sensitivity for women with mammographic dense breast?
- Study 5 and 6: Costs of SM+DBT and DM in a populations based screening program - is SM+DBT cost-effective?
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 29453 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | None (Open Label) |
Primary Purpose: | Diagnostic |
Official Title: | Digital Breast Tomosynthesis - The Future Screening Tool for Breast Cancer? |
Actual Study Start Date : | January 2016 |
Actual Primary Completion Date : | June 2018 |
Actual Study Completion Date : | May 2021 |

Arm | Intervention/treatment |
---|---|
Active Comparator: Digital Breast Tomosynthesis
Synthetic Mammography (SM) + Digital Breast Tomosynthesis (DBT) The SM+DBT will be independently read by two radiologists. A consensus meeting will decide whether to recall the woman or not. Women selected for further assessment (positive screening exam) will be recalled. |
Radiation: Synthetic Mammography + Digital Breast Tomosynthesis
Two-view tomosynthesis performed with GE Senoclaire 3D Breast Tomosynthesis.
Other Name: SM+DBT |
Active Comparator: Digital mammography
The digital mammograms will be independently read by two radiologists. A consensus meeting will decide whether to recall the woman or not.
|
Radiation: Digital mammography
Two-view digital mammography performed with GE Senoclaire 3D Breast Tomosynthesis.
Other Name: DM |
- Number of Participants With Screen-Detected Breast Cancer [ Time Frame: 36 months from start up of the trial ]Comparison of rates of screen-detected breast cancer in tomosynthesis versus digital mammography as performed in a population based screening program.
- Number and Percentage of Participants Screen-Detected Breast Cancer Among Participants Recalled for Further Assesment [ Time Frame: 36 months from start up of the trial ]Positive predictive value of recalls (number of screen-detected breast cancer among participants recalled for further assesment) for tomosynthesis versus digital mammography in a population based screening program.
- Number of Participants Recalled for Further Assesment Due to Mammographic Findings [ Time Frame: 36 months from start up of the trial ]Comparison of rate of recall for further assesment due to mammographic findings in tomosynthesis versus digital mammography as performed in a population based screening program.
- Incremental Costs of Screening With Tomosynthesis Versus Digital Mammography [ Time Frame: 36 months from start up of the trial ]The incremental cost per woman screened with digital breast tomosynthesis versus digital mammography in a population-based breast cancer screening program.
- Prognostic and Predictive Tumor Characteristics for Screen-Detected Breast Cancer [ Time Frame: 36 months from start up of the trial ]Distribution of characteristics among the women diagnosed with breast cancer screened with tomosynthesis versus digital mammography in a population based screening program.
- Number of Participants With Interval Breast Cancer [ Time Frame: 60 months from start up of the trial ]Rate of interval breast cancer among those screened with tomosynthesis versus digital mammography as performed in a population based screening program.
- Time Spent on Screen-Reading and Consensus Meetings [ Time Frame: 24 months from start up of the trial ]The time spent on screen-reading and consensus will be compared for tomosynthesis versus digital mammography
- Mammographic Features of Screen-Detected Breast Cancer [ Time Frame: 36 months from start up of the trial ]Distribution of characteristics among the women diagnosed with breast cancer screened with tomosynthesis versus digital mammography in a population based screening program.
- Radiation Doses When Screening With Tomosynthesis Versus Digital Mammography [ Time Frame: 24 months from start up of the trial ]Radiation doses will be measured for screening with tomosynthesis and digital mammography by an automated software, in milligray (mGy).

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Ages Eligible for Study: | 48 Years to 71 Years (Adult, Older Adult) |
Sexes Eligible for Study: | Female |
Accepts Healthy Volunteers: | Yes |
Inclusion Criteria:
- Informed consent
Exclusion Criteria:
- Breast implants

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT02835625
Norway | |
Haukeland University Hospital | |
Bergen, Hordaland, Norway, 0521 | |
Cancer Registry of Norway | |
Oslo, Norway, 0379 |
Principal Investigator: | Solveig Hofvind, Professor | Cancer Registry of Norway |
Documents provided by Cancer Registry of Norway:
Other Publications:
Responsible Party: | Cancer Registry of Norway |
ClinicalTrials.gov Identifier: | NCT02835625 |
Other Study ID Numbers: |
247941/H10 |
First Posted: | July 18, 2016 Key Record Dates |
Results First Posted: | January 15, 2021 |
Last Update Posted: | July 30, 2021 |
Last Verified: | January 2020 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Plan Description: | We will not share the data outside the project group |
Diagnostic Imaging Mammography Randomized Controlled Trial Tomosynthesis Early performance measures Recall |
Radiation dose Cancer detection Sensitivity Specificity Cost Economy |
Breast Neoplasms Neoplasms by Site Neoplasms Breast Diseases Skin Diseases |