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Trial registered on ANZCTR


Registration number
ACTRN12623001144606
Ethics application status
Approved
Date submitted
10/10/2023
Date registered
6/11/2023
Date last updated
30/04/2024
Date data sharing statement initially provided
6/11/2023
Type of registration
Prospectively registered

Titles & IDs
Public title
BreastScreen trial of hybrid tomosynthesis versus mammography screening
Scientific title
A co-designed prospective trial of the effectiveness of hybrid digital breast tomosynthesis/digital mammography compared to digital mammography in women presenting for routine screening at Maroondah BreastScreen
Secondary ID [1] 310767 0
none
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
breast cancer 331726 0
Condition category
Condition code
Cancer 328473 328473 0 0
Breast

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Current standard of care for breast screening is bilateral two-view (MLO and CC) digital mammography screening which represents 2-dimensional (2D) imaging. Intervention: 2D-mammography will be replaced with digital breast tomosynthesis (DBT, quasi-3D-mammography) acquisition for the MLO view only (2D-mammography images will be reconstructed from the DBT to provide synthetic 2D). Standard digital mammography will be acquired for the CC-view. This is referred to as ‘hybrid tomosynthesis/mammography’ screening or the ‘intervention screen’ in this trial. The process for the hybrid (intervention) screen is similar to the routine breast screen in that both involve transient compression of the breasts, x-ray acquisition by a radiographer, and take approximately 15 minutes.
Intervention code [1] 327172 0
Early detection / Screening
Comparator / control treatment
Standard of care breast screening: bilateral two-view (MLO and CC) digital mammography screening.
Control group
Active

Outcomes
Primary outcome [1] 336294 0
Breast cancer detection
Timepoint [1] 336294 0
BreastScreen obtains and records outcomes data usually within 2-8 weeks of screening visit, but this will vary depending on whether a participant is recalled to assessment (may take up to 12 weeks or longer). Trial dataset will be released to research team at pre-defined timepoints (at 5000 screens for intervention group; at completion of recruitment for all participants).
Primary outcome [2] 336295 0
Recall (to assessment)
Timepoint [2] 336295 0
BreastScreen obtains and records outcomes data usually within 2-8 weeks of screening visit, but this will vary depending on whether a participant is recalled to assessment (may take up to 12 weeks). Trial dataset will be released to research team at pre-defined timepoints (at 5000 screens for intervention group; at completion of recruitment for all participants).
Secondary outcome [1] 427716 0
Characteristics of detected breast cancers
Timepoint [1] 427716 0
BreastScreen obtains and records outcomes data usually within 2-8 weeks of screening visit, but this will vary depending on whether a participant is recalled to assessment (may take up to 12 weeks or substantially longer for the above-defined cancer characteristics (12-16 weeks)). These data will be released to research team at completion of recruitment of trial participants.
Secondary outcome [2] 427717 0

Opt-out rates (intervention group only)
Timepoint [2] 427717 0
At the time of attending the screening visit.
Secondary outcome [3] 427718 0
Screen-reading time
Timepoint [3] 427718 0
At screen-reading, usually performed within 2 days to 2 weeks of screen date.
Secondary outcome [4] 427719 0
Assessment testing (in women recalled to assessment)
Timepoint [4] 427719 0
Generally within 2-8 weeks of screening date but may take up to 12 weeks. Trial dataset will be released to research team at completion of recruitment of all trial participants.
Secondary outcome [5] 427720 0
Interval cancer rates
Timepoint [5] 427720 0
Minimum two years after attending for screening.

Eligibility
Key inclusion criteria
Women who are eligible to participate in the BreastScreen program and attending for a mammographic screen at Maroondah BreastScreen: East Ringwood screening site (intervention site) and Mont Albert screening site (standard screening site)
Minimum age
40 Years
Maximum age
No limit
Sex
Females
Can healthy volunteers participate?
No
Key exclusion criteria
- Women aged less than 40 years, or who are (or may be) pregnant or breastfeeding (not eligible for breast screening)
-Women deemed unable to provide informed consent (will have standard mammography screen).
-Women in whom a ‘pushback’ image cannot be obtained due to their breast implant will be excluded from the hybrid (intervention) screen due to technical issues and will have standard 2D-mammography.

Study design
Purpose of the study
Prevention
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Other
Other design features
Women attending for a mammographic screen at Maroondah BreastScreen (East Ringwood screening site) will be able to have the intervention (hybrid) screen (unless they 'opt out' of the study), and those attending Maroondah BreastScreen at the Mont Albert screening site will receive standard digital mammography.
Phase
Not Applicable
Type of endpoint/s
Statistical methods / analysis
Sample size
The primary outcome for the study is cancer detection rate (CDR) per 1,000 screens. Assuming a CDR of 6.6/1000 screens for mammography and a CDR of 9.1/1000 screens for DBT (CDR difference 2.5/1000), a minimum of 19,561 screenings are required in each group to detect this difference with 80% power. Allowing for around 1% incomplete assessments or data, we plan to recruit 20,000 screens per group.
Analysis Plan for primary outcome measures:
Cancer detection measures: the number of detected cancers will be reported, and the cancer detection rate (per 1,000 screens) will be estimated with 95% CI.
Recall measures: the number of recalls will be calculated as a proportion of the total number of screened women; the number of recalled women shown not to have cancer at assessment will be reported as a proportion of the total screened (minus those shown to have cancer) to estimate the false-positive recall percentage with 95% CI.
Stratified analyses:
Stratified analyses will be undertaken to report cancer detection rates and recall rates by breast density, Additional subgroup analyses will report these outcomes by age-groups and screening round (first versus repeat) strata.

Recruitment
Recruitment status
Recruiting
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
VIC

Funding & Sponsors
Funding source category [1] 314996 0
Charities/Societies/Foundations
Name [1] 314996 0
National Breast Cancer Foundation (NBCF)
Country [1] 314996 0
Australia
Funding source category [2] 314999 0
Government body
Name [2] 314999 0
National Health & Medical Research Council (NHMRC)
Country [2] 314999 0
Australia
Primary sponsor type
University
Name
University of Sydney
Address
Camperdown, NSW, 2006
Country
Australia
Secondary sponsor category [1] 317019 0
None
Name [1] 317019 0
Address [1] 317019 0
Country [1] 317019 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 313969 0
Eastern Health Human Research Ethics Committee
Ethics committee address [1] 313969 0
Ethics committee country [1] 313969 0
Australia
Date submitted for ethics approval [1] 313969 0
04/10/2023
Approval date [1] 313969 0
20/10/2023
Ethics approval number [1] 313969 0
LR23-059-102540 (Approval)

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 129962 0
Prof Nehmat Houssami
Address 129962 0
Room 325, Building A27, Faculty of Medicine & Health, University of Sydney, NSW, 2006
Country 129962 0
Australia
Phone 129962 0
+61 0419 273510
Fax 129962 0
Email 129962 0
Contact person for public queries
Name 129963 0
Nehmat Houssami
Address 129963 0
Room 325, Building A27, Faculty of Medicine & Health, University of Sydney, NSW, 2006
Country 129963 0
Australia
Phone 129963 0
+61 0419 273510
Fax 129963 0
Email 129963 0
Contact person for scientific queries
Name 129964 0
Nehmat Houssami
Address 129964 0
Room 325, Building A27, Faculty of Medicine & Health, University of Sydney, NSW, 2006
Country 129964 0
Australia
Phone 129964 0
+61 0419 273510
Fax 129964 0
Email 129964 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
Not permitted by data custodian (BreastScreen Victoria)


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.