Unimodal to Multimodal Prehabilitation in Gastric Cancer Surgery: Systematic Review of Randomised Controlled Trials.

Prehabilitation prior to gastric cancer resection aims to optimise pre-operative physical and nutritional status to improve perioperative resilience. However, the current evidence-base is fragmented. This review synthesized randomized controlled trial (RCT) evidence evaluating effectiveness of prehabilitation interventions prior to gastric cancer resection and characterized reported outcomes. A systematic review was conducted following PRISMA guidelines (PROSPERO registration -CRD420251233981). MEDLINE, Embase, CENTRAL, Web of Science, and CINAHL were searched up to August 2025. Eligible studies were RCTs investigating unimodal or multimodal prehabilitation interventions (minimum duration 7 days) prior to gastric cancer resection. Two reviewers independently performed study selection, data extraction, and risk-of-bias assessment. Heterogeneity precluded meta-analysis and results were synthesized narratively. Fourteen RCTs were included: four multimodal, and ten unimodal interventions (nutritional (n = 9), spirometry (n = 1)), duration range (7-days to 15-weeks). Fifty-three unique outcomes were reported across five domains: clinician/observer-reported outcomes, performance outcomes, patient-reported outcomes, biomarkers, and non-health outcomes. Multimodal prehabilitation programs suggest potential benefits; fewer postoperative complications, and improved functional capacity. Short-duration unimodal nutritional interventions demonstrated mixed effects, although immune-nutrition and targeted supplementation reduced infectious complications in malnourished patients. Findings were limited by risk-of-bias (some concerns (n = 7), high (n = 7)). Prehabilitation in gastric cancer surgery demonstrated a potential benefit, particularly when delivered as multimodal interventions. However, the evidence base is limited by substantial heterogeneity, variable methodological quality, and inconsistent outcome reporting. Development of a disease-specific core outcome set is urgently required, in addition to adequately powered, risk-stratified trials to advance evidence synthesis and implementation of gastric cancer prehabilitation.