Published online Sep 27, 2022. doi: 10.4240/wjgs.v14.i9.1008
Peer-review started: January 20, 2022
First decision: April 10, 2022
Revised: April 22, 2022
Accepted: August 24, 2022
Article in press: August 24, 2022
Published online: September 27, 2022
Processing time: 245 Days and 1.8 Hours
Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) is an innovative approach to hepatectomy. The surgical trauma experienced by ALPPS is relatively high. In addition, stage-I ALPPS separates the right and left liver lobes and ligates the right hepatic vein, which causes inflammatory reactions, hypoxia, and tumor necrosis, resulting in a unique and complex immune microenvironment for tumor cells.
The trends and effects of tumor-infiltrating lymphocytes (TIL) residing or recruited in the tumor microenvironment (TME) are still unexplored in studies on ALPPS for hepatocellular carcinoma (HCC).
From an immunological perspective, the immunological effects exerted by the unique TME formed during the treatment of HCC by ALPPS, such as anti-tumor effects or tumor-induced immunosuppression, were investigated to further evaluate the safety and efficacy of ALPPS in treating massive HCC and conduct an in-depth study of TILs in the TME.
Patients of the ALPPS and hemi-hepatectomy groups were screened using propensity score matching. Immunofluorescence staining was performed to detect and quantify TILs in tumors and adjacent tissues in these two groups of patients. Trends in TILs in peripheral blood during the perioperative period were compared between the two groups.
The proportion of tumor necrosis volume at postoperative day 7 after stage-I ALPPS was significantly higher than the pre-operative value (P = 0.024). The proportion of tumor necrosis volume was significantly higher in the high CD8+ T-cell infiltrated group than in the low group before surgery for stage-I ALPPS (P = 0.048).
From an immunological point of view, ALPPS is safe and feasible for treating right lobe massive HCC. The level of TIL infiltration during the perioperative period is dynamically balanced, and the ALPPS procedure itself does not lead to severe immunosuppression due to reduced TIL infiltration and pathological changes in peripheral blood immune components.
Many studies on TIL therapy for tumors have entered clinical trials. As an important branch of tumor immunotherapy, TIL therapy is one of the potential directions for the future development of medicine.