The CONVERGENCE trial protocol: a phase II/III trial for conversion surgery for gastric cancer with peritoneal metastases

Background The benefit of surgical resection in addition to systemic therapy in patients with gastric/gastroesophageal cancer and peritoneal metastases (GCPM) is controversial. This CONVERGENCE trial aims to study the potential benefits of conversion surgery in patients with peritoneal metastases.Methods This is a prospective, pragmatically designed, multicentre, randomized, investigator-initiated phase II/III trial. Patients with synchronous GCPM who have undergone either systemic therapy (including 1 L chemotherapy +/- targeted therapy +/- immunotherapy) +/- peritoneal directed chemotherapy with favourable response would be randomized in 1:1 ratio to Arm 1 (Conversion surgery followed by systemic +/- peritoneal directed chemotherapy or Arm 2 (continual systemic +/- peritoneal directed chemotherapy). In the initial Phase II trial, 136 patients will be recruited and randomized. The primary endpoint is overall survival; main secondary endpoints include progression-free survival, R0 resection and complete cytoreduction rates, surgical morbidity/mortality and quality of life outcomes. If pre-defined thresholds of improved overall survival are met, the trial will expand to adequately power a phase III randomized controlled trial (n = 300).Discussion If survival benefit in conversion gastrectomy is demonstrated, this could potentially be a new standard of care for patients with peritoneal metastases from gastric or gastroesophageal junction cancer. Conversely, negative findings may lead to the avoidance of unnecessary surgical procedures and morbidity in these patients.Trial registration NCT07241715.