Long-term survival outcomes from a phase II trial of perioperative capecitabine plus oxaliplatin for advanced gastric cancer with extensive lymph node metastases: OGSG 1701

BACKGROUND: Patients with advanced gastric cancer and para-aortic and/or bulky lymph node metastases have extremely poor prognosis after surgery alone. The OGSG1701 phase II trial evaluated the efficacy and safety of perioperative administration of capecitabine and oxaliplatin (CapeOx). Short-term results showed promising response and resection rates. Herein, we report the final survival outcomes. METHODS: This multicenter, single-arm, phase II trial enrolled patients with histologically proven, HER2-negative or unknown gastric cancer with para-aortic (no.16a2/16b1) and/or bulky lymph node metastases. Patients received three cycles of preoperative CapeOx followed by gastrectomy with D2 ± para-aortic lymphadenectomy, and five cycles of postoperative CapeOx. The primary endpoint was response rate; the key secondary endpoints included overall survival (OS) and progression-free survival (PFS). RESULTS: Thirty patients from 14 institutions were enrolled between 2018 and 2022. At a minimum follow-up of 36 months, the 3- and 5-years OS rates were 79.0% (95% confidence interval [CI], 59.0-90.0%) and 61.0% (95% CI 38.9-77.1%), respectively. Median OS was 64.9 months (95% CI 41.2-not estimable). The 3 years PFS rate was 46.7% (95% CI 28.4-63.0%), and the median PFS was 29.0 months (95% CI 9.4-not estimable). No additional treatment-related deaths occurred during the long-term follow-up. CONCLUSIONS: Perioperative CapeOx therapy resulted in encouraging long-term survival in patients with advanced gastric cancer and extensive nodal metastasis. These findings support its potential role as a perioperative strategy for biologically high-risk gastric cancer, with an acceptable safety profile.