Inflammatory and tumor stimulating responses after laparoscopic sigmoidectomy

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

BACKGROUND

Laparoscopic surgery (LS) is hypothesized to result in milder proinflammatory reactions due to less severe operative trauma, which may contribute to the observed clinical benefits after LS. However, previous systematic reviews and meta-analyses on the impact of LS on immunocompetence are outdated, limited and heterogeneous. Therefore, the humoral response after laparoscopic and open colorectal cancer (CRC) resections was evaluated in a comprehensive systematic review and meta-analysis.

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).

RESULTS

Twenty RCTs with 1131 participants were included. Narrative synthesis and meta-analysis up to 8 days after surgery was performed. Quantitative synthesis found concentrations to be significantly lower after LS at 0-2 h after surgery (IL-8), at 3-9 h (CRP, IL-6, IL-8, TNFα) and at postoperative day 1 (CRP, IL-6, IL-8, VEGF). At 3-9 h, IL-6 was notably lower in the LS group by 86.71 pg/ml (mean difference [MD] - 86.71 pg/ml [- 125.05, - 48.37], p < 0.00001). Combined narratively, 13 studies reported significantly lower concentrations of considered parameters in LS patients, whereas only one study reported lower inflammatory markers (for CRP and IL-6) after OS.

CONCLUSION

The increase in postoperative concentrations of several proinflammatory parameters was significantly less pronounced after LS than after OS in this meta-analysis. Overall, the summarized evidence reinforces the view of a lower induction of inflammation due to LS.

Postoperative inflammatory response in colorectal cancer surgery: a meta-analysis

PURPOSE

Surgical removal of the cancerous tissue remains the cornerstone of curative treatment for colorectal cancer and results in an inflammatory response. An exaggerated inflammatory response has been implicated in the promotion of tumor proliferation and has shown associations with postoperative complications. Literature on the preferred surgical technique to minimize inflammatory response is inconclusive. Therefore, the aim of this study was to assess the inflammatory response and postoperative incidence of infectious complications following surgery for colorectal cancer.

METHODS

Embase, PubMed, and Cochrane databases were searched for RCTs that reported inflammatory parameters as a function of surgical modality only. Data related to CRP or IL-6 levels on postoperative days 1 and 3 and data related to postoperative infections were subject to a pairwise meta-analysis to compare open versus laparoscopic techniques.

RESULTS

The literature search and screening process yielded 4151 studies. Ten studies met criteria, including 568 patients. Only studies on laparoscopic and open surgery were found. Pooled analyses found lower Il-6 and CRP levels on postoperative day 1 and lower CRP levels on postoperative day 3 for laparoscopic surgery compared to open surgery. However, there was no difference in incidence of postoperative infectious complications.

CONCLUSION

The findings of this study indicate a superior inflammatory profile for laparoscopic surgery compared to an open approach for colorectal cancer surgery. For future research, it would be worthwhile to conduct a randomized controlled trial to compare the postoperative inflammatory response and related clinical outcomes between minimally invasive surgical approaches, including laparoscopic and robot-assisted surgery.

Immunological effects of hybrid minimally invasive versus conventional open pancreatoduodenectomy - A single center cohort study

BACKGROUND

Minimally invasive surgery is a field of rapid development. Evidence from randomized controlled trials in visceral surgery however still falls short of attesting unequivocal superiority to laparoscopic procedures over conventional open approaches with regard to postoperative outcome. The aim of this study was to explore the perioperative immune status of patients undergoing hybrid minimally invasive or conventional open pancreatoduodenectomy in a prospective cohort study.

MATERIAL AND METHODS

Subtyping, quantification and functional analysis of circulating immune cells and determination of cytokine-levels in blood samples from patients receiving either hybrid minimally invasive (laPD) or conventional open pancreatoduodenectomy (oPD) was performed. Samples were taken from 29 patients (laPD: n = 14, oPD: n = 15) prior, during and up to six weeks after surgery. Cells were analyzed by flow cytometry, cytokines/chemokines were measured by proximity extension and enzyme-linked immunoassays.

RESULTS

Open surgery induced higher levels of circulating inflammatory CD14⁺⁺CD16⁺ intermediate monocytes. In contrast, hybrid minimally invasive resection was accompanied by increased numbers of circulating regulatory CD4⁺CD25⁺CD127^low T-cells and by a reduced response of peripheral blood CD3⁺CD4⁺ T-cell populations to superantigen stimulation. Yet, rates of postoperative morbidity and infectious complications were similar.

CONCLUSIONS

In summary, the results of this exploratory study may suggest a more balanced postoperative inflammatory response and a better-preserved immune regulation after hybrid minimally invasive pancreatoduodenectomy when compared to open surgery. Whether these results may translate to or be harnessed for improved patient outcome needs to be determined by future studies including larger cohorts and fully laparoscopic or robotic procedures.