Controversies of colonic stenting in obstructive left colorectal cancer: a critical analysis with meta-analysis and meta-regression

Abstract

Purpose: After almost three decades since the first description of colonic stents, the controversies of its safe application continue to impede the readiness of adoption by clinicians for malignant left bowel obstruction. This review seeks to address some of the controversial aspects of stenting and its impact on surgical and oncological outcomes.

Methods: Medline, Embase, and CNKI were searched for articles employing SEMS for left colonic obstruction. Outcomes analyzed include success rates, complications, and long-term survival. Pooled risk ratio (RR) and 95% confidence interval (CI) were estimated.

Results: 36 studies were included with 2002 patients across seven randomized controlled trials and 29 observational studies. High technical (92%) and clinical (82%) success rates, and low rates of complications, including perforation (5%), were found. Those with > 8% perforation rates had poorer technical success rates than those with ≤ 8%, but there were no significant differences in 90-day in-hospital mortality and three and 5-year overall and disease-free survival. A significant increase was found in technical (RR = 1.094; CI, 1.041-1.149; p < 0.001) and clinical (RR = 1.158; CI, 1.064-1.259; p = 0.001) success rates when the duration between stenting and surgery was ≥ 2 weeks compared to < 2 weeks, but there were no significant differences in perforation rates, 90-day in-hospital mortality, and long-term survival.

Conclusions: Colonic stenting is safe and effective with high success rates and low complication rates. However, outcomes of higher perforation rates and optimal timing from stent till surgery remain unclear, with only a few studies reporting on these outcomes, leaving areas for future research.

Keywords: Bridge to surgery; Colonic neoplasms; Meta-analysis; Palliative; Self-expanding metallic stent.