Preoperative colonoscopy after colonic stenting as a bridge to surgery for obstructive colorectal cancer: a systematic review and meta-analysis

Colonic stenting may allow preoperative evaluation of the proximal colon in patients with obstructive colorectal cancer. We assessed colonoscopy completion, diagnostic yield, procedure-related adverse events, and changes in planned colorectal surgery. We searched PubMed, Embase, Scopus, Web of Science, and the Cochrane Library through September 19, 2026. Studies of preoperative colonoscopy after self-expandable metallic stent placement as a bridge to surgery were appraised using Joanna Briggs Institute (JBI) checklists. Proportions were pooled using random-effects binomial generalized linear mixed models. Technical completion among documented attempts was the primary outcome. Certainty of evidence was assessed using GRADE. Eleven predominantly observational studies were included. Technical completion was 81.3% (95% CI, 72.2%–87.9%; 7 studies, 261 attempts; I² = 62.7%). Pathway completion was 73.1% (49.0%–88.5%; 8 studies, 452 patients; I² = 94.9%). Synchronous colorectal cancer, including in situ disease, was identified or confirmed in 7.3% (3.3%–15.3%) after completed colonoscopy and 4.8% (2.5%–8.9%) per attempt in the exploratory sensitivity analysis. Adenoma detection was 36.3% (28.3%–45.1%; 3 studies), and planned surgery changed in 2.5% of attempts (0.4%–15.2%; 5 studies). The pooled proportion with any adverse event was 2.2% (0.4%–12.0%; 5 studies, 240 patients), excluding Kim because overlap between bleeding and perforation was unknown. Two perforations were reported among 288 patients in studies reporting this outcome. The certainty of evidence was very low for all six main pooled outcomes. Preoperative colonoscopy was usually completed once attempted and identified findings relevant to surgical planning. Variation in pathway completion and limited safety evidence support individual assessment before the procedure. PROSPERO CRD420261478358.