Long-Term Outcomes of Neoadjuvant Chemotherapy in Locally Advanced Gastric Cancer/Esophagogastric Junction Cancer: A Systematic Review and Meta-Analysis.

BACKGROUND Neoadjuvant chemotherapy (NAC) has been defined as any preoperative chemotherapy scheme aiming to reduce tumor staging and to control preoperative micrometastasis, which has been extensively used as a treatment for resectable gastric cancer. However, its effect on the long-term survival of patients with locally advanced gastric cancer (AGC) or esophagogastric junction cancer (EGC) remains unknown. OBJECTIVE This study aimed at investigating the long-term efficacy of NAC in locally AGC/EGC. METHODS The following databases were searched for articles published from their inception up to April 2020: PubMed, Web of Science, EBSCO, and Cochrane library. The primary outcomes were overall survival (OS) and progression-free survival (PFS). RESULTS A total of 19 articles were included in this meta-analysis, with a total of 4,446 patients. The results showed that NAC increased the patients' 3-year OS (HR, 0.56; 95%CI, 0.21-0.91; P<0.001), 3-year PFS (HR, 0.76; 95%CI, 0.66-0.87; P<0.001), 5-year OS (HR, 0.71; 95% CI, 0.64-0.78; P<0.001), and 5-year PFS (HR, 0.70; 95% CI, 0.61-0.79; P<0.001) respectively. Besides, subgroup analysis showed that Asian countries have benefited significantly from NAC (HR, 0.65; 95%CI, 0.55-0.74; P<0.001), and other countries have also benefited (HR, 0.79; 95%CI, 0.68-0.89; P<0.001). CONCLUSIONS Compared with adjuvant chemotherapy and surgery alone, NAC can improve the long-term survival outcomes (OS and PFS) of patients with resectable AGC or EGC.