Clinical efficacy of neoadjuvant chemotherapy regimens FLEEOX vs. XELOX in patients with initially unresectable advanced gastric cancer: a propensity score analysis

Purpose: This study was designed to assess the effectiveness of FLEEOX (5-Fu, leucovorin, etoposide, oxaliplatin, and epirubicin) compared with XELOX (capecitabine and oxaliplatin) as neoadjuvant chemotherapy (NAC) for initially unresectable advanced gastric cancer (AGC). Methods: This study reviewed patients who underwent FLEEOX or XELOX for initially unresectable AGC. To reduce the bias in patient selection, we conducted propensity score match (PSM) with 1: 1 ratio. Tumor and pathological response, surgical characteristics, chemotherapy-related toxicity and overall survival (OS) were analyzed. Results: From January 2004 to December 2012, 436 patients were enrolled; 99 pairs of patients were generated after PSM. The tumor response rates were 80.8% and 68.7% in FLEEOX and XELOX (P=0.018). 80 patients (80.8%) in FLEEOX and 63 (63.6%) in XELOX received radical resection (P< 0.001). The pathological complete response rate and R0 rate were 11.1% and 69.7% in FLEEOX, respectively, while 4.8% and 38.4% in XELOX (P<0.001). Median OS time was longer in FLEEOX (30.0 vs. 25.1 months, P<0.001). In addition, more toxicities occurred in FLEEOX, including leukocytopenia (17.2% vs. 7.1%, P=0.024), nausea (17.2% vs. 6.1%, P=0.012) and vomiting (22.2% vs. 10.1%, P=0.016). The overall toxicity rate was higher in FLEEOX (71.7% vs. 35.4%, P<0.001). Conclusion: The FLEEOX regimen as NAC for patients with initially unresectable AGC can improve tumor response rate, radical resection rate, R0 rate, and OS as compared to XELOX regimen. More chemotherapy-related toxicity was observed in FLEEOX group, although no chemotherapy-related deaths and aborting were observed. Further randomized clinical trials on the FLEEOX regimen are necessary.