LBA78 Overall survival of perioperative or postoperative adjuvant oxaliplatin with S-1 versus adjuvant oxaliplatin with capecitabine in locally advanced gastric or gastro-oesophageal junction adenocarcinoma undergoing D2 gastrectomy: An updated analysis of RESOLVE trial

The RESOLVE study demonstrated a disease-free survival (DFS) benefit from perioperative SOX compared to adjuvant CapOx in patients with gastric or gastro-oesophageal junction (G/GOJ) adenocarcinoma who underwent D2 gastrectomy. Here, we aim to update on the 5-year overall survival (5yOS%) results. The phase III, open-label, randomized controlled RESOLVE study (NCT01534546) enrolled patients with stage cT4aN+M0 or cT4bNanyM0 G/GOJ adenocarcinoma. Patients were 1:1:1 randomly assigned to adjuvant CapOx, adjuvant SOX, or perioperative SOX and underwent standard gastrectomy with D2 lymphadenectomy. The adjuvant CapOx group received 8 cycles of oxaliplatin (130 mg/m2, d1) with capecitabine (1000 mg/m2, bid, d1-14). The adjuvant SOX group received oxaliplatin and oral S-1 at a dose depending on body surface area (40-60 mg bid, d1-14). The perioperative SOX group received 3 cycles of preoperative SOX plus 5 cycles of postoperative SOX followed by 3 cycles of S-1 monotherapy. The primary endpoint was 3-year DFS, and second endpoints included 5yOS% and safety. Between 08/2012 and 02/2017, 1022 patients were included in mITT population and analyzed. With a median follow up time of 62.8 months, 495 recurrences and 416 deaths were observed by 07/04/2022. Perioperative SOX improved 5yOS% compared with adjuvant CapOx (60.0% vs. 52.1%; HR 0.79, 95%CI [0.62-1.00]; p=0.049). Adjuvant SOX was not inferior to postoperative CapOx (61.0% vs. 52.1%; HR 0.77, 95%CI [0.61-0.98]; p=0.033). Perioperative SOX improved 5yDFS% compared with adjuvant CapOx (53.2% vs. 45.8%; HR 0.79, 95%CI [0.63-0.98]; p=0.034). Adjuvant SOX was not inferior to adjuvant CapOx (50.8% vs. 45.8%; HR 0.86, 95%CI [0.69-1.06]; p=0.164). No additional adverse events were observed. The update on the RESOLVE survival analysis revealed improved survival in patients with G/GOJ adenocarcinoma undergoing D2 gastrectomy with perioperative SOX therapy compared to adjuvant CapOx, and adjuvant SOX was not inferior to adjuvant CapOx.