Abstract OT1-13-01: BIOSYM - A Feasibility Randomised Controlled Trial Comparing Biological Matrices with Synthetic Meshes in Women Undergoing One Stage Implant Based Breast Reconstruction. ClinicalTrials.gov Identifier: NCT05449691
Authors: Goyal Amit , Garreffa Emanuele , Newcombe Robert , Harder Helena , Rose Janice , Jenkins Valerie 
Published: March 2023

Abstract
Research question: Is it feasible to conduct a multicentre randomised controlled trial (RCT) to test the long-term efficacy and safety of biological matrices compared with synthetic meshes in women undergoing one-stage mesh and implant breast reconstruction as standard care. Background: The use of biological and synthetic meshes in implant-based breast reconstruction has become standard care and is the most widely used procedure in the UK. However, there is limited evidence on patient outcomes and how safe each type of mesh is in the long-term to guide patient choices and surgeon decision-making. Aims: To assess patient and clinician acceptance, recruitment rate, and compliance with randomly allocated intervention. We will evaluate completeness of data on proposed future main study outcomes. The standard deviation (SD) of patient reported ‘satisfaction with breasts’ score on Breast Q will inform sample size calculations for the main study. To inform economic evaluation of main study, we will evaluate completeness of EQ-5D-5L and recommendation of an alternative preference-based QoL measure to be used in a definitive trial. Methods: Design: Pragmatic, feasibility, randomised controlled trial. Target population: Women undergoing mastectomy for breast cancer or risk reduction and immediate one-stage breast reconstruction using implant and mesh as standard care. Randomisation: Women will be randomised to biological matrix or synthetic mesh in a 1:1 ratio. Measurement of outcomes Complications: such as infection, wound breakdown, readmission, reoperation, unplanned surgery, skin flap necrosis, implant loss, seroma, pain, capsular contracture and haematoma will be recorded at 3- and 6-months post-surgery. Patient reported outcomes: Women will complete Breast Q and EQ-5D-5L questionnaires at randomisation, 3- and 6-months post-surgery. Sample size: By recruiting 60 (out of 120) we will be able to estimate a participation rate of 50% of women offered the trial to within a 95% confidence interval of +/-9% and a completion rate of 90% (54 of 60) within a 95% confidence interval of (80%, 95%). Additionally, 60 participants will be enough to estimate the SD for sample size calculation for the main study. Timelines for delivery: Recruitment start date: 01 September 2022. Anticipated Impact and Dissemination: The BIOSYM research question has been identified as a key research gap by Association of Breast Surgery (UK). If we can demonstrate feasibility, the definitive trial will provide high quality long-term data on patient outcomes and safety of each type of mesh. Results will be published in peer-reviewed high impact journals and, with PPI partners we will produce patient-facing summaries for a lay audience. The results will inform specialist and NICE guidelines.
Citation Format: Amit Goyal, Emanuele Garreffa, Robert Newcombe, Helena Harder, Janice Rose, Valerie Jenkins. BIOSYM - A Feasibility Randomised Controlled Trial Comparing Biological Matrices with Synthetic Meshes in Women Undergoing One Stage Implant Based Breast Reconstruction. ClinicalTrials.gov Identifier: NCT05449691 [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr OT1-13-01.