Peritoneal Carcinomatosis of Gastric Origin - Treatment Possibilities.

Background: Peritoneal carcinomatosis of gastric origin is challenging to diagnose and treat. This disease is often misdiagnosed in the early stages using a non-invasive technique. Conventional surgery is unsuitable for treatment of patients with peritoneal seeding and positive peritoneal cytology. Peritoneal recurrence is the most frequent cause of therapeutic failure. The effectiveness of chemotherapy is low due to the plasma-peritoneal barrier. Cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy (HIPEC) is the standard treatment for pseudomyxoma peritonei and mesothelioma and improves overall survival and disease-free survival. This approach is also widely used to prevent and treat peritoneal carcinomatosis of gastric origin.

Purpose: This article aims to provide a short summary of the contemporary role of cytoreductive surgery and HIPEC for treatment of gastric cancer patients. Theoretically, there are four possible applications and indications. First, palliative application to improve quality of life without prolongation of overall survival. This application mainly affects malignant ascites. Second, therapeutic application using a combination of gastrectomy/cytoreductive surgery and HIPEC to treat advanced disease including peritoneal metastases. Localized peritoneal seeding is the only indication for this application (maximum peritoneal cancer index of 10-12 or Cy+). Third, adjuvant/prophylactic application in patients at high risk of peritoneal recurrence, typically those with T3, T4, N+ disease (without peritoneal seeding). Fourth, neoadjuvant application using a combination of repeated HIPEC and chemotherapy with the aim of decreasing peritoneal seeding and enabling radical surgery. In this indication, HIPEC is often replaced by pressurized intraperitoneal aerosol chemotherapy.