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 enzymelinked 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+CD127lowT-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. (c) 2021 IAP and EPC. Published by Elsevier B.V. All rights reserved.