[Feasibility and safety of pressurized intraperitoneal aerosol chemotherapy (PIPAC) in patients with peritoneal metastatic gastrointestinal cancer: a preliminary report].

<b>Objective:</b> This study aimed to summarize and analyze the preliminary application experience of a novel pressurized intraperitoneal aerosol chemotherapy (PIPAC) device in patients with peritoneal metastases of gastrointestinal malignancies. <b>Methods:</b> In this descriptive case series study, four patients with pathologically confirmed peritoneal metastatic gastrointestinal malignancies were enrolled, receiving PIPAC treatment at Guangdong Provincial People's Hospital from December 2024 to February 2025. The PIPAC treatment was performed five times on these patients . Key procedural steps included equipment preparation, operation platform construction, cytologic examination of ascites, Peritoneal Cancer Index (PCI) scoring, biopsy of peritoneal metastases, drug preparation, connection and testing of the PIPAC device, PIPAC treatment, and aerosol evacuation. Preoperative and postoperative clinical data were collected and analyzed to assess the safety and feasibility of PIPAC treatment. <b>Results:</b> 3 males and 1 female patients were enrolled; median age was 57 (range, 36-70) years old; median body mass index was 22.5 (range, 18.0-24.6) kg/m², and the preoperative Eastern Cooperative Oncology Group (ECOG) score was 1 for all cases. Four patients successfully completed the five PIPAC treatments without any intraoperative adverse events. The PIPAC treatment time ranged from 34 minutes to 36 minutes, with a median preoperative PCI score of 18 (range, 5-25). The average Peritoneal Regression Grading Score (PRGS) before the first and second PIPAC treatments were 2.1±0.8 and 1.7±0.6, respectively. The median Visual Analog Scale (VAS) scores for pain on postoperative days 1, 2, and 3 were 2 (range, 2-4), 1 (range, 0-2), and 1 (range, 0-2), respectively. All patients resumed the oral intake and ambulation on the first postoperative day, with a postoperative hospital stay of 3 days. No postoperative complications or perioperative death occurred. <b>Conclusion:</b> The preliminary study results indicate that the use of the novel PIPAC device for the treatment of peritoneal metastases of gastrointestinal malignant tumors is safe and feasible.