Prophylactic surgery plus hyperthermic intraperitoneal chemotherapy (HIPEC CO2) versus standard surgery for gastric carcinoma at high risk of peritoneal carcinomatosis: short and long-term outcomes (GOETH STUDY)—a collaborative randomized controlled trial by ACOI, FONDAZIONE AIOM, SIC, SICE, and SICO

INTRODUCTION: At the time of diagnosis, 15–20% of gastric carcinomas are in stage T4 or T4b. Furthermore, 5–20% of patients undergoing potentially curative surgery suffer from synchronous or metachronous peritoneal metastases. To date, neither surgery nor systemic chemotherapy successfully controls peritoneal dissemination, offering a limited impact on survival. Peritoneal metastases are in fact responsible for death in around 60% of gastric cancer patients. Several Eastern studies in the past have focused on hyperthermic intraperitoneal chemotherapy (HIPEC) as a prophylactic measure in patients with serosal extension, nodal involvement, and positive peritoneal fluid cytology. Therefore, a new multimodal therapeutic strategy based on aggressive surgery plus new locoregional treatment may prolong survival in this particular clinical scenario. METHODS: This study compares the efficacy of prophylactic surgery (radical gastric resection, appendectomy, resection of the round ligament of the liver, and bilateral adnexectomy) plus hybrid CO2 HIPEC system versus standard surgery in patients with T3-T4 N0-N + gastric adenocarcinoma. Patients will be randomly assigned (1:1 ratio) to the experimental arm or standard surgery. The primary endpoint is to establish the difference in disease-free survival between the groups. The secondary objective is to compare the safety and tolerability of prophylactic surgery plus HIPEC CO(2) versus standard surgery. DISCUSSION: Considering the poor prognosis of patients with peritoneal dissemination from gastric cancer, a prophylactic strategy to prevent peritoneal metastases may be beneficial. In patients with gastric cancer at high risk of peritoneal carcinomatosis, we propose aggressive surgical treatment with radical gastrectomy, removal of organs at risk of harbouring tumour cells, and HIPEC. TRIAL REGISTRATION: ClinicalTrials.gov NCT03917173. Registered on 16 April 2019. Protocol version: v1, March 27, 2019. Protocol number: IRFMN-GCC-7813. EudraCT number: 2019–001478-27. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13063-022-06880-y.