Colorectal Disease Poster Prize Session

Background: Intra-operative electron radiotherapy (IOERT) directly delivers a large fraction of radiation to at-risk margins during surgery.However, the precise benefit of IOERT in patients with locally advanced and locally recurrent colorectal cancer (LACC/ LRCC) is unclear.This study aimed to provide an updated summary of the current evidence available regarding IOERT as part of multimodality treatment of LACC and LRCC.Methods: This systematic review update was prospectively registered on PROSPERO (CRD42023438184).An electronic literature search was carried out using Ovid (MEDLINE), EMBASE, Web of Science, and the Cochrane Library databases for studies from July 2011 to April 2024.The inclusion criteria were adult patients who received IOERT as part of multi-modal treatment for LACC or LRCC.The primary outcome was overall survival (OS), disease free survival (DFS) and local control (LC) at 5 years.Secondary outcomes included post-operative complications.Results: 16 new studies were identified since the previous analysis, ABSTRACT particularly for high-risk patients.Further studies are not needed to evaluate the primary outcomes in this meta-analysis.