Surgical safety of preoperative or perioperative immune checkpoint inhibitors in colorectal cancer surgery: protocol for a systematic review and meta-analysis focusing on anastomotic leakage
Jing Zhang, Yuhong Zhang, Baiwang Zhu, Zhengqi Jiang, Bo YiIntroduction
Immune checkpoint inhibitors (ICIs) are increasingly used before colorectal cancer surgery, particularly for mismatch repair-deficient or microsatellite instability-high tumours. Their surgery-specific safety, especially the risk of anastomotic leakage (AL), remains uncertain. We aim to synthesise AL and other postoperative outcomes after preoperative or perioperative ICI therapy.
Methods and analysis
We will search PubMed/MEDLINE, Embase, Web of Science, Scopus, CENTRAL, ClinicalTrials.gov, CNKI and the WHO International Clinical Trials Registry Platform from inception to July 2026 without language restrictions. We will include randomised and non-randomised comparative studies, cohort and case–control studies and single-arm studies reporting postoperative outcomes after preoperative or perioperative ICI therapy; case reports and case series with fewer than five surgically treated patients will be excluded. The primary outcome is AL among patients who underwent bowel resection with a constructed intestinal anastomosis. Two reviewers will independently screen records, extract data and assess risk of bias using design-appropriate validated tools. Comparative and non-comparative studies will be analysed separately: risk ratios from comparative studies will be pooled in random-effects models, and single-arm AL rates will be pooled as proportions using a binomial-logit generalised linear mixed model. Heterogeneity, prespecified subgroup analyses, sensitivity analyses and the certainty of the evidence (Grading of Recommendations Assessment, Development and Evaluation) will be reported.
Ethics and dissemination
Ethics approval is not required because only published aggregate data will be used. Results will be submitted to a peer-reviewed journal and presented at scientific meetings. Extraction materials, analytical code and the derived dataset will be shared in an open repository with the completed review.
PROSPERO registration number
CRD420261426134.