PS5-09-14: Rossini-platform: a 'basket factorial multi arm multi stage (mams)' platform trial in surgical site infection - the breast surgery pillar

Abstract Introduction: Surgical Site Infection (SSI) is the most common postoperative complication costing the UK National Health Service (NHS) more than £700million annually. SSI after breast surgery profoundly impacts patients, for example through readmission for antibiotics, further surgery for washout, and an increased number of hospital visits. SSI may also adversely affect cosmetic outcomes, dramatically impacting on quality of life and long-term wellbeing. Finally, SSI may delay adjuvant treatments such as radiotherapy and chemotherapy, and recent evidence from large cohort studies suggests that complications after breast surgery, may increase the risk of breast cancer recurrence. Few interventions to reduce SSI are underpinned by high quality evidence and consequently there is wide variation in practice across the UK. Methods: The National Institute for Health & Care Excellence (NIHR) Health Technology Assessment (HTA) funded ROSSINI-Platform study (NIHR163832) is a multi-speciality ‘Basket Factorial Multi Arm Multi Stage (MAMS)’ platform trial, in which full-scale RCTs are delivered in parallel within 6 different surgical specialties including breast surgery, cardiothoracics, neurosurgery, obstetrics, vascular limb (amputation) and vascular groin. It is the largest surgical trial ever funded by the NIHR and will utilise active learning and cross-cohort transfer of interventions (and/or combinations of), that suggest benefit. Selected initial interventions in breast surgery include prophylactic antibiotics (vs no antibiotics); Granudacyn® wound irrigation (vs standard of care including no wash or other types of irrigation) and; Dialkylcarbamoyl chloride (DACC)-coated dressings (Leukomed® Sorbact®) (vs standard of care including all other types of dressings/glue/steristrips and no dressings). Negative wound pressure therapy (NWPT) is not allowed in the standard of care arm as these dressings are being trialed in the vascular and cardiothoracic pillars initially. It is likely as the trial progresses that NWPT may be evaluated in higher risk breast surgery wounds. Breast surgery SSI risk will be stratified according to BMI, smoking status, diabetes, immunosuppression, and receipt of neoadjuvant chemotherapy and/or immunotherapy. Results: All adult patients undergoing breast cancer resectional surgery are eligible for recruitment with only patients undergoing primary whole breast reconstruction excluded. Implant reconstruction has a higher associated risk of infection and because of the significant consequence of implant loss, UK surgeons are not in equipoise to randomise these patients to a trial of SSI interventions. A sample size of 4280 breast surgery patients (whole trial 25,924) is required to show an absolute risk reduction of 2% from a baseline SSI rate of 5%. The primary outcome of SSI within 30 days of surgery, will be assessed at hospital discharge and/or remotely through a pre-existing Central Digital Wound Hub (CDWH), augmented by questionnaires and wound photographs collected via a patient-facing App (or via email/telephone if preferred). Secondary outcomes include health related quality of life, a cost-effectiveness analysis and other wound complications. Conclusions: The methodologically unique approach of ROSSINI-Platform employs a highly efficient trial design, to provide practice changing results and improve patient outcomes in a more time and cost-effective manner than traditional trials. The results have the potential to change and standardise SSI prevention practice both nationally and internationally. The trial will open in the UK in September 2025. Citation Format: K. Fairhurst, S. Potter, S. McIntosh, T. Pinkney. Rossini-platform: a 'basket factorial multi arm multi stage (mams)' platform trial in surgical site infection - the breast surgery pillar [abstract]. In: Proceedings of the San Antonio Breast Cancer Symposium 2025; 2025 Dec 9-12; San Antonio, TX. Philadelphia (PA): AACR; Clin Cancer Res 2026;32(4 Suppl):Abstract nr PS5-09-14.