Prospective randomized phase II study of FOLFIRI versus FOLFOX7 in advanced gastric adenocarcinoma: a Chinese Western Cooperative Gastrointestinal Oncology Group Study

Until now, no standard chemotherapy has been widely accepted for advanced gastric cancer (GC). The current research aimed to compare folinic acid, fluorouracil with irinotecan (mFOLFIRI) or with oxaliplatin (mFOLFOX7) as first-line treatments in patients with locally advanced GC in an open, randomized, phase II study. Previously untreated metastatic or recurrent GC patients with measurable disease received mFOLFIRI (arm A) or mFOLFOX7 (arm B) every 2 weeks. The defined second-line treatment was mFOLFOX7 for arm A and mFOLFIRI for arm B. Primary endpoint was progression-free survival (PFS), and secondary endpoints were overall survival (OS), disease control rate (DCR) and toxicity. The evaluable population consisted of 128 patients (54 in arm A; 74 in arm B). Median PFS of arm A was 2.9 months (m) (95% confidence interval, CI, 1.9 to 4.1 m) versus 4.1 m (95% CI, 3.2 to 4.8 m) for arm B (p = 0.109). Median OS was 9.9 months (95% CI, 6.0 to 13.5 m) for arm A versus 12.0 m for arm B (95% CI, 10.3 to 13.7m; p = 0.431). DCRs for arm A and arm B were 59.3% and 66.3%, respectively (p = 0.850). In subgroup analysis of the patients who completed both treatment lines per protocol, the median first-line PFS was 2.1 m for the mFOLFIRI/mFOLFOX7arm versus 8.0 m for the mFOLFOX7/mFOLFIRI arm (p = 0.053), and the median second-line PFS values were 1.2 m versus 5.1 m (p = 0.287). Total PFS and OS were 8.1m and 11.0 m for the mFOLFIRI/mFOLFOX7 group compared with 12.2m and 20.2 m for the mFOLFOX7/mFOLFIRI group (p = 0.008, p = 0.030). Both regimens were well-tolerated with acceptable and manageable toxicities. Hence, there was no significant difference in the PFS or DCR. However, mFOLFOX7 followed by mFOLFIRI might have a better OS.