Management Strategies for Malignant Left-Sided Colonic Obstruction: A Systematic Review and Network Meta-analysis of Randomized Controlled Trials and Propensity Score Matching Studies.

BACKGROUND

The optimal treatment strategy for left-sided malignant colonic obstruction remains controversial. Emergency colonic resection has been the standard of care; however, self-expanding metallic stenting as a bridge to surgery may offer short-term advantages, although oncological concerns exist. Decompressing stoma may provide a valid alternative, with limited evidence.

OBJECTIVE

To perform a systematic review and Bayesian arm random-effects model network meta-analysis comparing the approaches for management of malignant left-sided colonic obstruction.

DATA SOURCES

A systematic review of PubMed, Embase, Cochrane Library, and Google Scholar databases was conducted from inception to August 22, 2023.

STUDY SELECTION

Randomized controlled trials and propensity score-matched studies.

INTERVENTIONS

Emergency colonic resection, self-expanding metallic stent, and decompressing stoma.

MAIN OUTCOME MEASURES

Oncologic efficacy, morbidity, successful minimally invasive surgery, primary anastomosis, and permanent stoma rates.

RESULTS

Nineteen of 5225 articles identified met our inclusion criteria. Stenting (risk ratio 0.57; 95% credible interval, 0.33-0.79) and decompressing stomas (risk ratio 0.46, 95% credible interval: 0.18-0.92) resulted in a significant reduction in the permanent stoma rate. Stenting facilitated minimally invasive surgery more frequently (risk ratio 4.10; 95% credible interval, 1.45-13.13) and had lower overall morbidity (risk ratio 0.58; 95% credible interval, 0.35-0.86). A pairwise analysis of primary anastomosis rates showed increased stenting (risk ratio 1.40; 95% credible interval, 1.31-1.49) compared with emergency resection. There was a significant decrease in the 90-day mortality with stenting (risk ratio 0.63; 95% credible interval, 0.41-0.95) compared with resection. There were no differences in disease-free and overall survival rates, respectively.

LIMITATIONS

There is a lack of randomized controlled trials and propensity score matching data comparing short-term and long-term outcomes for diverting stomas compared to self-expanding metallic stents. Two trials compared self-expanding metallic stents and diverting stomas in left-sided malignant colonic obstruction.

CONCLUSIONS

This study provides high-level evidence that a bridge-to-surgery strategy is safe for the management of left-sided malignant colonic obstruction and may facilitate minimally invasive surgery, increase primary anastomosis rates, and reduce permanent stoma rates and postoperative morbidity compared with emergency colonic resection.