Intraperitoneal paclitaxel with systemic S-1 plus oxaliplatin for advanced or recurrent gastric cancer with...

Patients with peritoneal metastasis from gastric cancer show poor prognosis with standard systemic chemotherapy. This prospective multicenter phase II clinical trial was performed to evaluate the efficacy and safety of intraperitoneal paclitaxel combined with systemic S-1 plus oxaliplatin for patients with advanced or recurrent gastric cancer with peritoneal metastasis.

Patients with advanced or recurrent gastric cancer with histologically or radiologically confirmed peritoneal metastases were eligible for the study. The chemotherapy regimen consisted of eight cycles of intraperitoneal paclitaxel 80 mg/m² on days 1 and 8, combined with 80 mg/m² S-1 for days 1-14, and 100 mg/m² oxaliplatin on day 1, repeated every 21 days. The primary endpoint was 6-month progression-free survival. One-year progression-free and overall survival, response rate, and safety were set as the secondary endpoints.

In total, 28 patients were included in the study, of which 24 were analyzed, with the exception of those lost to follow-up and withdrawal of consent. The 6-months progression-free survival was 82.6 % (95 % CI: 68.5-99.6 %). The one-year progression-free and overall survival rates were 69.6 % (95 % CI: 53.1-91.2 %) and 76.9 % (95 % CI: 61-97 %), respectively. The overall response rate was 41.67 %. The hematologic toxicity profile showed grade 3/4 hematologic toxicities such as leukopenia (20.8 %), neutropenia (41.7 %), and thrombocytopenia (8.3 %). The only non-hematologic adverse event was grade 3 diarrhea. Three (12.5 %) patients experienced intraperitoneal chemoport-related adverse events.

Bidirectional intraperitoneal paclitaxel with systemic S-1 plus oxaliplatin shows promising efficacy and safety in the treatment of peritoneal metastatic gastric cancer.