Impact of laparoscopic versus open surgery on humoral immunity in patients with colorectal cancer: a systematic review and meta-analysis.

"Declarations DisclosuresAnnika Bohne, Elena Grundler, Helge Knüttel, Vinzenz Völkel and Alois Fürst have no conflicts of interest or financial ties to disclose. Disclosures Annika Bohne, Elena Grundler, Helge Knüttel, Vinzenz Völkel and Alois Fürst have no conflicts of interest or financial ties to disclose."

"Funding Open Access funding enabled and organized by Projekt DEAL. The authors have no funding to disclose."

"The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) 2020 checklist was used when writing the report []. The protocol of this systematic review was registered prospectively in PROSPERO under registration number CRD42021264324, with a draft search strategy published in a public repository []. Methods: Included were randomized controlled trials (RCTs) measuring parameters of humoral immunity after LS compared to open surgery (OS) in adult patients with CRC of any stage. MEDLINE, Embase, Web of Science (SCI-EXPANDED), Cochrane Library, Google Scholar, ClinicalTrials.gov and ICTRP (World Health Organization) were systematically searched. Risk of bias (RoB) was assessed using the Cochrane RoB2 tool. Weighted inverse variance meta-analysis of mean differences was performed for C-reactive protein (CRP), interleukin (IL)-6, IL-8, tumour necrosis factor (TNF)α and vascular endothelial growth factor (VEGF) using the random-effects method. Methods were prospectively registered in PROSPERO (CRD42021264324)."