A Systematic Mapping Review of Core Outcome Reporting in Surgical Research for Oesophageal Cancer.

Oesophageal carcinoma is a rising global health burden, with surgical resection and perioperative chemotherapy forming the cornerstone of curative treatment. However, uncertainty persists regarding the optimal surgical approach, partly due to heterogeneity in outcome reporting, which hinders data synthesis and evidence-based decision-making. To address this, a core outcome set (COS) for oesophageal cancer surgery was developed through international consensus among clinicians and patients. This study systematically evaluates the uptake of these core outcomes in contemporary surgical research. A systematic review was conducted of randomised controlled trials and prospective cohort studies investigating oesophagectomy for oesophageal cancer, published between 2010 and 2024. The reporting of ten COS-recommended outcomes was assessed across eligible studies. Fifty-eight studies involving 22 260 patients were included (39 cohort studies; 19 RCTs). No study reported all 10 core outcomes. The median number of core outcomes reported was 4 (interquartile range 3-5). The frequency of individual core outcome reporting was as follows: in-hospital mortality (86%), conduit necrosis/leak (81%), respiratory complications (79%), overall survival (30%), ability to eat and drink (44%), quality of life (26%), inoperability (23%), reflux symptoms (21%), severe nutritional effects (19%), and need for reintervention (16%). No improvement in core outcome reporting was observed over the study period. Promoting COS implementation and improving methodological rigour is essential to ensure that future research reflects the priorities of both clinicians and patients, and facilitates meaningful evidence synthesis.