Individualized riskbased imaging surveillance after breast-conserving surgery for breast cancer (IRIS)– a multicenter registry-based randomized trial
Charlotta Wadsten, Åsa Wickberg, Hanna Sartor, Anne Andersson, Eva Vikhe Patil, Jenny Heiman, Anders BerglundAbstract
Introduction
The effectiveness of current follow-up recommendations after breast cancer remain uncertain. Early detection of local recurrence improves survival, but surveillance strategies are largely uniform despite significant differences in recurrence risk. Interval recurrences detected between scheduled visits are more likely in younger patients and those with non-luminal subtypes. In addition, mammography has lower sensitivity in breast cancer survivors compared to healthy women. Supplemental imaging methods, such as magnetic resonance imaging (MRI) or contrast-enhanced mammography (CEM), may improve detection in high-risk groups. This study aims to evaluate whether more sensitive imaging methods enable earlier detection of second breast cancers after breast-conserving surgery (BCS) in patients with high recurrence risk.
Methods
A multicenter, open-label, R-RCT including patients from the National Quality Register for Breast Cancer. Women aged <50 years, or women of any age with HER2-positive or triple-negative breast cancer who have undergone BCS, will be randomized to standard follow-up with annual mammography for five years or the same regimen with the addition of MRI or CEM at years 2 and 4. The primary endpoint is the number of interval-detected ipsilateral and contralateral second breast cancers within five years. Secondary endpoints include recurrence stage, survival, recall and biopsy rates, false-positive findings, and health-related quality of life. Based on power calculations (4 versus 2%), 2300 patients (1:1) are required to achieve 80% power.
Results
Recruitment will begin in 2026, with first interim results expected in 2029.
Discussion
There is an unmet need for individualized breast cancer surveillance guidelines. This study aims to help address this evidence gap.