Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) in the treatment of gastric cancer: Feasibility, Efficacy and Safety - a Systematic Review and Meta-Analysis

Abstract

Background: Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) is an emerging technique capable of delivering chemotherapy directly to the peritoneum through a pressurized aerosol. It has gained increasing attention due to its applicability in treating peritoneal carcinomatosis (PC) of several primary tumour origins, with gastric cancer (GC) being among the most prevalent. Therefore, we aimed to systematically investigate the therapeutic role of PIPAC in the context of treating gastric cancer peritoneal metastasis (GCPM). Methods: The present systematic review and meta-analysis was conducted according to the PRISMA 2020 guidelines. Three databases were searched (Pubmed, Web of Science and SCOPUS). We performed a meta-analysis of relative risks and mean differences to compare patients who underwent 1 or 2 PIPAC with patients completing 3 or more procedures, assessing the length of hospitalization, operative time, occurrence of adverse events, Peritoneal Regression Grading Score (PRGS), Peritoneal Cancer Index (PCI), ascites volume variation, and mean overall survival. Heterogeneity was assessed using the I2 statistic. Results: Eighteen studies were included in the qualitative analysis and four in the quantitative analysis. Patients with 3 or more PIPAC procedures experienced shorter hospitalization (MD = -1.2; 95%CI (-1.9; -0.5); p<0.001), higher rates of complete or partial histopathological response (RR=1.77 95%CI (1.08; 2.90); p=0.023), and significantly improved mean overall survival (MD=6.0; 95%CI (4.2; 7.8); p<0.001). Other assessed outcomes showed no statistically significant differences. Conclusion: Overall, PIPAC demonstrated efficacy in carefully selected patients, exhibiting enhanced histopathologic response rates and promising impacts on overall survival, in patients undergoing multiple cycles, without exacerbating hospital stay duration. Emphasizing the need for randomized controlled trials and precise selection criteria, this study contributes to refining PIPAC's implementation in clinical settings.