Perioperative Outcomes from a Phase II Study of Robotic Cytoreduction and Hyperthermic Intraperitoneal Chemotherapy...

Traditional open cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for peritoneal limited metastatic gastric cancer (GC) is associated with significant morbidity and prolonged recovery. We hypothesized that a robotic approach may significantly reduce postoperative recovery.

Prospective phase II, single-arm trial conducted in patients with synchronous, low volume (PCI ≤ 7) peritoneal limited metastatic GC who had completed ≥ 4 months of systemic chemotherapy were enrolled. Patients were treated with laparoscopic HIPEC followed by robotic cytoreduction, gastrectomy, and HIPEC with 175 mg/m2 paclitaxel and 100 m2/mg cisplatin. The primary end point was hospital length of stay (LOS). The secondary outcomes were 90-day postoperative complications, readmission, reoperations, and mortality.

Between January 2023 and March 2025, 20 patients met eligibility criteria and were enrolled. Two patients subsequently progressed and were deemed ineligible for complete cytoreduction and were thus excluded leaving 18 evaluable patients. A total of 2 patients had positive peritoneal cytology only, and 16 had peritoneal carcinomatosis. Patients completed a median of 9 (IQR 8-10) cycles of neoadjuvant chemotherapy, most (72.2.%) commonly FOLFOX +/- nivolumab. The median peritoneal carcinomatosis index (PCI) at CRS/Gastrectomy and HIPEC was 6 (IQR 3-7). A complete cytoreduction was achieved in 100%. The median blood loss was 300 ml (IQR 200-450 ml) and the red blood cell (RBC) transfusion rate was 22.2%. The median operative time was 688 min (642-722 min) and the primary end point of hospital LOS was 5 days (4-6). The 90-day major morbidity, and readmission rate was 38.9% and 27.8%. There was a single (5.6%) 90-day reoperation and death. There were negligible risks attributed to HIPEC with only two (11.1%) grade IV cytopenia and one (5.9%) acute kidney injury.

Robotic cytoreduction, gastrectomy, and HIPEC for low volume peritoneal limited metastatic gastric cancer, in this highly selected patient population, is associated with favorable outcomes such as decreased hospital LOS and less blood loss/blood transfusions compared with the open approach in the literature. We continue to enroll and follow patients to assess long-term oncologic outcomes.