Immune changes induced by periampullary adenocarcinoma are reversed after tumor resection and modulate the postoperative survival

Background Tumor growth encompasses multiple immunologic processes leading to impaired immunity. Regarding cancer surgery, the perioperative period is characterized by an additional immunosuppression that may contribute to poor outcomes. In this exploratory study, we assessed plasma parameters, characterizing the perioperative immunity with a particular focus on their prognostic value. Patients and methods 31 patients undergoing pancreatoduodenectomy were enrolled (adenocarcinoma of the pancreatic head and its periampullary region: n=24, benign pancreatic diseases n=7). Abundance and function of circulating immune cells and the plasma protein expression were analyzed in blood samples taken pre- and postoperatively using flow cytometry, ELISA and Proximity Extension Assay. Results Prior to surgery, an increased population of Tregs, a lower frequency of intermediate monocytes, a decreased portion of activated T-cells and a reduced response of T-cells to stimulation in vitro were associated with cancer. On the first postoperative day, both groups showed similar dynamics. The preoperative alterations did not persist six weeks postoperatively. Moreover, several preoperative parameters correlated with the postoperative survival. Conclusion Our data suggest systemic immunologic changes in adenocarcinoma patients, which are reversible six weeks after tumor resection. Additionally, the preoperative immune status affects the postoperative survival. In summary, our results implicate prognostic and therapeutic potential, justifying further trials on the perioperative tumor immunity to maximize the benefit of surgical tumor therapy.