The impact of the optimal timing for surgery after stent placement in patients with malignant large bowel obstruction (MLBO) on postoperative clinical outcomes-update 2025: a systematic review and meta-analysis

Malignant large bowel obstruction (MLBO) is a serious presentation of colorectal cancer. Self-expandable metallic stent (SEMS) placement can decompress the colon and facilitate elective resection in selected patients, but the most appropriate stent-to-surgery interval remains uncertain. This updated systematic review and meta-analysis compared postoperative outcomes across three clinically relevant intervals. This systematic review was designed and reported in accordance with PRISMA 2020. PubMed, Embase, Web of Science Core Collection, SinoMed, and the Cochrane Library were searched from inception to June 30, 2025. Two reviewers independently screened studies and extracted data. Eligible patients underwent SEMS placement followed by tumor resection and were categorized as ≤ 7 days, 8–14 days, or > 14 days. For single-arm dichotomous outcomes, event proportions were transformed to log odds and pooled using the generic inverse-variance method; intraoperative blood loss was synthesized as a pooled mean. Differences among timing subgroups were assessed using χ² tests for subgroup differences. Thirty-three studies involving 1,130 patients were included. Odds Ratio differed significantly between timing subgroups for stoma formation: 8–14 days, 0.09 (95% confidence interval (CI) 0.06–0.15) versus > 14 days, 0.23 (95% CI 0.15–0.35; P for subgroup difference = 0.005), and versus ≤ 7 days, 0.20 (95% CI 0.12–0.34; P = 0.03). For anastomotic leakage, Odds Ratio were 0.03 (95% CI 0.01–0.06) at 8–14 days and 0.08 (95% CI 0.04–0.16) at > 14 days (P = 0.03), whereas ≤ 7 versus 8–14 days did not differ significantly (P = 0.78). No significant subgroup differences were found for pooled mean intraoperative blood loss, overall postoperative complications, or 30-day mortality. Most evidence was observational. Surgery performed 8–14 days after stent placement showed the most favorable overall pattern among the evaluated intervals, but the evidence does not establish definitive superiority over alternative timing strategies. The 8–14-day interval may be considered a potentially favorable surgical window when clinically appropriate, pending confirmation in prospective comparative studies. PROSPERO CRD420261474024 (retrospectively registered).