OBJECTIVE: Despite advances in systemic therapy, outcomes of patients with gastric cancer (GC) peritoneal carcinomatosis (PC) remain poor, in part because of poor penetrance of systemic therapy into peritoneal metastasis due to the plasma-peritoneal barrier and anarchic intra-tumoral circulation. Hence, regional treatment approach with administration of chemotherapy directly into the peritoneal cavity (intraperitoneal, IP) under various conditions, combined with or without cytoreductive surgery (CRS) has remained an area of significant research interest. The purpose of this review is to provide high-level evidence for regional treatment approaches in the management of GCPC with limited peritoneal disease.
METHODS: A review of the current literature and ongoing clinical trials for regional IP therapies for GCPC was performed. Studies included in this review comprise of phase III randomized controlled trials, non-randomized phase II studies, high-impact retrospective studies, and active ongoing clinical trials for each available IP modality.
RESULTS: The three common IP approaches are heated intraperitoneal chemotherapy (HIPEC), normothermic intraperitoneal chemotherapy (NIPEC) and more recently introduced, pressurized intraperitoneal aerosolized chemotherapy (PIPAC). These IP approaches have been combined with systemic therapy and/or CRS with varying degrees of promising results, demonstrating evidence of improvements in survival rates and peritoneal disease control. Patient selection, optimization of systemic therapy, and completeness of cytoreduction have emerged as major factors influencing the design of contemporary and ongoing trials.
CONCLUSIONS: IP chemotherapy has a clear role in the management of patients with GCPC, and when combined with CRS in appropriately selected patients has the potential to significantly improve survival. Ongoing and upcoming IP therapy clinical trials hold great promise to shape the treatment paradigm for GCPC.

Pancreatic cancer represents one of the leading causes of cancer-related death worldwide. Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC), normothermic intraperitoneal chemotherapy (NIPEC), and pressurized intraperitoneal aerosol chemotherapy (PIPAC) has been proven with curative intent mainly for other tumors and there is a lack of consensus regarding possible benefits also in pancreatic cancer. The present systematic review and meta-analysis aim to provide an up-to-date overview of the effectiveness and safety of intraperitoneal treatments in the management of pancreatic cancer.
A systematic review of articles was conducted according to PRISMA and AMSTAR-2 guidelines. 11 studies were included in the analysis.
We included in our analysis 212 patients subdivided in three groups: 64 in the HIPEC group (57 with prophylactic intent and 7 with curative intent), 55 in the PIPAC group and 93 in the NIPEC group. Primary outcomes were represented by survival rates; we evidenced at an observation time of three years a survival of 24% in the HIPEC group (25.5% in the prophylactic arm and 6.2% in the curative arm), 5.3% in the PIPAC group and 7.9% in the NIPEC group.
HIPEC could be considered as a promising technique for prophylaxis and treatment of peritoneal metastasis (PM) in case of borderline resectable and locally advanced disease. Increased survival rates emerged without additional morbidity when surgical resection and CRS are possible. In addition, our data about PIPAC and NIPEC as palliative treatment in unresectable disease seems to identify more favorable survival rates compared to literature.