RESUMEN
Exercise training is emerging as a supportive treatment strategy in surgical oncology, but its effects remain uncertain in patients with gastrointestinal cancer. The primary objective of this systematic review and meta-analysis was to evaluate the effects of perioperative exercise training on gastrointestinal cancer-specific mortality, recurrence, and surgical outcomes (postoperative complications, hospitalization, surgical stress) in patients with gastrointestinal cancer. Randomized or quasi-randomized controlled trials evaluating the effects of perioperative exercise training versus control in patients with GI cancer were eligible. MEDLINE, EMBASE, CENTRAL, CINAHL, PEDro, and SPORTDiscus were systematically searched on June 20, 2020. Data were synthesized using random-effects meta-analyses. Risk of bias was assessed using the Cochrane risk of bias tool 2, and the certainty of evidence was assessed using GRADE. Study selection, data extraction, risk of bias, and GRADE assessments were performed independently by two authors. Ten randomized controlled trials comprising 448 participants with gastrointestinal cancer were eligible. Meta-analyses indicated no statistical effects of exercise on postoperative complications (risk ratio: 1.11, 95% CI: 0.84; 1.47), readmissions (risk ratio: 2.76; 95% CI: 0.00, 9394.76), or postoperative length of stay (difference in means: -0.47, 95% CI: -17.2; 16.2 days). None of the eligible studies assessed gastrointestinal cancer-specific mortality or recurrence. Overall risk of bias was high or of some concerns in all studies, and the certainty of evidence was very low. The effects of perioperative exercise on cancer-specific and surgical outcomes are unknown in patients with gastrointestinal cancer due to lack of studies and very low certainty of evidence.