122 Background: Previous phase II trial with combination therapy of S-1 plus oxaliplatin (SOX) demonstrated high response rate and well tolerability in patients with untreated advanced gastric cancer. The aim of this phase II trial was to evaluate the efficacy and safety of SOX as neoadjuvant chemotherapy for locally advanced gastric cancer (AGC). Methods: Eligibility criteria included a histologically proven AGC with stage IIIb, IIIc (AJCC 7th edition), at least 1 measurable lesion, no prior chemotherapy, ECOG 0∼2, adequate hepatic, renal, and bone marrow function. Enrolled patients were staged by EUS and CT. The neoadjuvant chemotherapy consisted of 3-4 cycles of oxaliplatin (130 mg/m2) on day 1 and S-1 (80 mg/m2/day) for 14 days with 7 days rest. After chemotherapy, the patients underwent surgery. Results: From Dec 2009 to Sep 2010, 35 patients (IIIb; 19pts, IIIc; 16pts) were enrolled. The median age of the patients was 54.6 years (range; 20-72 y). All patients were available for evaluating the clinical responese and adverse events. The overall response rate was 68.5% (1CR, 23 PR, 9 SD, 2 PD). 32 patients underwent surgical resection. Of them, 27 patients underwent standard D2 surgery and 5 patients had palliative surgery. 25 patients had R0 resection. Postoperative pathological examination showed that most of the surgical patients were in T4a stage. According to Lauren classification, 71.9% patiens (23/32pts) were diffuse type, SOX showed higher respons rate (1CR, 20 PR, 2 SD, RR: 91.3%) among these patients. Major grade 3/4 hematological toxicities were anemia (5.7%), neutropenia (5.7%) and liver dysfunction (8.6%) and non-hematological toxicities were anorexia (5.7%) and vomiting (11.4%). But most of the adverse events were managable. Conclusions: Neoadjuvant chemotherapy with S-1 plus oxaliplatin (SOX) showed high response rate and and R0 resection rate for locally advanced GC, especially for diffuse type patients. All the patients did not have severe toxicity during the process of chemotherapy. This is the preliminary results, and the survival benefit in locally advanced GC patients that respond to SOX neoadjuvant chemotherapy needs to be addressed by a randomized-controlled trial. No significant financial relationships to disclose.
Primary results of multicenter phase II study of neoadjuvant chemotherapy with S-1 and oxaliplatin for locally advanced gastric cancer (Neo G-SOX PII)
