At ESMO 2025, Judith S. Quik presented the PERISCOPE II trial during Mini Oral Session 1 on GI tumours (upper digestive), introducing a multicentre randomized study in gastric cancer with limited peritoneal metastases.
Background
About one-third of patients with gastric cancer (GC) present with synchronous peritoneal metastases (PM), a group with poor prognosis. Gastrectomy combined with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) has been considered promising, but until now had not been tested against systemic therapy alone in a randomized controlled trial.
Methods
PERISCOPE II was a multicentre RCT. After 3–4 cycles of systemic chemotherapy (with or without immuno- or targeted therapy), patients with resectable cT3/T4a gastric adenocarcinoma and limited PM (PCI <7) and/or positive peritoneal cytology who had no progression were randomized 1:1 to continue systemic therapy (standard arm, S) or undergo gastrectomy plus CRS/HIPEC (experimental arm, E). The perfusion protocol used oxaliplatin 460 mg/m² at 41 °C for 30 min and docetaxel 50 mg/m² at 37 °C for 90 min. The primary endpoint was overall survival (OS); secondary endpoints included progression-free survival, treatment-related toxicity, and quality of life.
Results
From 2017–2024, 102 patients were enrolled; the study was closed early (September 2024) for futility. Analyses included ITT n=101 and per-protocol n=81.
Efficacy
- Intention-to-treat OS: 16.6 months in the standard arm vs 15.7 months in the CRS/HIPEC arm (HR 1.1, p=0.7).
- Per-protocol OS: 17.3 months in the CRS/HIPEC arm vs 15.2 months in the standard arm (HR 0.65, p=0.12). A multivariate model in the PP cohort showed HR 0.7, p=0.22.
Safety
There were 49 serious adverse events (SAEs) overall (p<0.001): 4 SAEs in the standard arm (3 patients) and 45 SAEs in the CRS/HIPEC arm (22 patients), most commonly ileus (17%) and anastomotic leakage (13%) in the experimental arm. Three treatment-related deaths (6%) occurred, all in the CRS/HIPEC arm.
You can read the full abstract here.
Conclusions
In patients with gastric cancer and limited peritoneal metastases, gastrectomy plus CRS/HIPEC did not improve overall survival compared with continued systemic therapy and was associated with a substantially higher rate of serious adverse events. These randomized data do not support routine CRS/HIPEC in this setting; effective systemic therapy and careful trial-based selection remain the priority.
You can read about INTEGRATE IIb Trial at ESMO 2025: Regorafenib Plus Nivolumab vs Chemotherapy in Advanced Gastric and GEJ Cancer on OncoDaily.
