Self-expanding metal stents for the treatment of malignant colon obstruction from extra-colonic malignancy versus intra-colonic malignancy: a systematic review and meta-analysis.

BACKGROUND AND AIMS: The relative utility of self-expanding metal stent (SEMS) insertion for malignant colon obstruction (MCO) due to extra-colonic malignancy (ECM) versus intra-colonic malignancy (ICM) is understudied. METHODS: A systematic search was done from inception-April 2021 to identify reports of safety and efficacy of SEMS insertion for the treatment of MCO-ECM versus MCO-ICM. A meta-analysis of proportions, comparative meta-analysis to compute relative risks (RR), and mean differences (MD) was performed. Subgroup analyses and influence analyses were conducted. The certainty in estimates of effect(s) was assessed using the GRADE approach. RESULTS: Eight non-randomized studies were identified; 46% (39-53%) and 63% (59-67%) of patients in the ECM and ICM groups were male. Most obstructions were in the rectosigmoid colon in both ECM and ICM groups. SEMS insertion in MCO-ECM was associated with an increased risk of technical failure compared to MCO-ICM (RR 2.92; 1.13-7.54; Certainty: Very Low). Risk of clinical failure of SEMS was higher in MCO-ECM compared to MCO-ICM (RR 2.88; 1.58-2.52; Certainty: Very Low). The risk of clinical failure remained significant throughout the influence analysis, as well as on subgroup analysis. There was no significant difference in the risk of adverse events or luminal perforation with SEMS insertion among patients with MCO-ECM and MCO-ICM. On influence analysis, removal of one study unveiled a significant increase in the risk of luminal perforation in MCO-ECM (RR 3.22; 1.44-7.19; p = 0.004). CONCLUSION: SEMS for MCO-ECM may have a technical success rate comparable to or questionably worse than MCO-ICM, with low certainty in estimate of effects. SEMS deployment in MCO-ECM carries a higher risk of clinical failure, with a questionably higher risk of luminal perforation.

The Impact of Postoperative Complications on Long-Term Oncological Outcomes Following Curative Resection of Colorectal Cancer (Stage I-III): A Systematic Review and Meta-Analysis.

Background and objective The incidence of post-surgical complications (PSCs) after curative resection of non-metastatic colorectal cancer (CRC) is very widespread and evident. Some studies suggest that PSCs often predict poor long-term oncological outcomes. However, the available data on the topic is often controversial. The aim of this systematic review and meta-analysis was to study the effect of postoperative complications (POCs) on long-term oncological outcomes following curative resection of non-metastatic (stage I-III) CRC. Methods A comprehensive search of MEDLINE® and Excerpta Medica dataBASE (EMBASE) databases was performed via the Ovid platform, by using controlled vocabulary as well as natural language terms for POCs, outcomes, and CRC. Two authors independently screened the studies and extracted data. Conflicts were resolved by discussion among authors and also independently with the help of a third author. Meta-analysis was performed using a random-effects model (REM) to calculate pooled estimates for overall survival (OS), disease-free survival (DFS), and overall recurrence. Results Overall, 3,836 studies were initially screened, and 16 studies involving 37,192 patients were ultimately selected for final inclusion in the analysis. Meta-analysis of these studies showed that PSCs following non-metastatic CRC surgery predicted worse OS rates [hazard ratio (HR): 1.36; 95% CI: 1.15-1.61; p<0.00001], DFS (HR: 1.41; 95% CI: 1.11-1.80; p<0.00001), and overall recurrence (HR: 1.19; 95% CI: 1.04-1.37; p=0.01). Conclusion Based on our findings, PSCs predict poor OS rates, DFS, and overall recurrence following curative resection of non-metastatic CRC.