Review of Regional Therapies for Gastric Cancer with Peritoneal Metastases.

Abstract

Simple SummaryGastric cancer is usually diagnosed at late stages and is associated with poor five-year survival rates. Metastasis to the peritoneal cavity is common and leads to even worse outcomes. Currently, the mainstay of treatment for metastatic gastric cancer is systemic chemotherapy or supportive care. These recommendations remain despite evidence that suggests systemic therapy has poor penetration into the abdominal cavity, limiting efficacy against peritoneal disease. Newer treatments have been developed to address this problem, specifically regional therapies aimed at delivering chemotherapy directly into the peritoneal cavity to eradicate tumor cells. These novel therapies include hyperthermic intraperitoneal chemotherapy, normothermic intraperitoneal chemotherapy, and pressurized intraperitoneal aerosolized chemotherapy. Regional therapies may also be combined with surgery to remove both macroscopic and microscopic disease. Although more clinical trials are needed to evaluate its efficacy, early studies have shown promising outcomes with intraperitoneal chemotherapy.Gastric cancer carries a poor prognosis and is a leading cause of cancer-related mortality worldwide. Patients with gastric cancer who develop peritoneal metastases have an even more dismal prognosis, with median survival time measured in months. Since studies have demonstrated that systemic chemotherapy has poor penetration into the peritoneum, multimodal treatment with intraperitoneal chemotherapy has been proposed for the treatment of peritoneal metastases and has become the foundation for newer therapeutic techniques and clinical trials. These include heated intraperitoneal chemotherapy (HIPEC) with cytoreductive surgery (CRS), which involves the application of heated chemotherapy into the abdomen with or without tumor debulking surgery; normothermic intraperitoneal chemotherapy (NIPEC), in which non-heated chemotherapy can be delivered into the abdomen via a peritoneal port allowing for repeat dosing; and pressurized intraperitoneal aerosolized chemotherapy (PIPAC), a newer technique of pressurized and aerosolized chemotherapy delivered into the abdomen during laparoscopy. Early results with intraperitoneal chemotherapy have shown promise in increasing disease-free and overall survival in select patients. Additionally, there may be a palliative effect of these regional therapies. In this review, we explore and summarize these different intraperitoneal chemotherapy treatment regimens for gastric cancer with peritoneal metastases.