The benefits of neoadjuvant therapy for patients with resectable pancreatic cancer: an updated systematic review and meta-analysis

Neoadjuvant therapy (NAT) was effective in improving overall survival (OS) of borderline resectable pancreatic cancer. However, its application in resectable pancreatic cancer remains controversial. This study aimed to determine whether NAT has a greater advantage over conventional upfront surgery (US) in terms of resection rate, R0 resection rate, positive lymph node rate, and OS. We identified articles before October 7, 2022, by searching four electronic databases. The studies included in the meta-analysis all met the inclusion and exclusion criteria. The Newcastle–Ottawa scale was used to evaluate the quality of the articles. OS, DFS, resection rate, R0 resection rate and positive lymph nodes rate were extracted. Odds ratio (OR), hazard ratio (HR) and 95% confidence intervals (CI) were calculated, and sensitivity analysis and publication bias were used to assess the sources of heterogeneity. In total, 24 studies, involving 1384 (35.66%) patients assigned to NAT and 2497 (64.43%) patients assigned to US, were included in the analysis. NAT could effectively prolong OS (HR 0.73, 95% CI 0.65–0.82, P < 0.001) and DFS (HR 0.72, 95% CI 0.62–0.84, P < 0.001). Subgroup analysis results of 6 randomized controlled trials (RCTs) also showed that RPC patients could benefit from NAT in the long term (HR 0.72, 95% CI 0.58–0.90, P = 0.003). NAT decreased resection rate (OR 0.43, 95% CI 0.33–0.55, P < 0.001), but was associated with increased R0 resection rate (OR 2.05, 95% CI 1.47–2.88, P < 0.001) and decreased positive lymph node rate (OR 0.38, 95% CI 0.27–0.52, P < 0.001). Although the application of NAT increases the risk of patients not being able to undergo surgical resection, it can prolong the OS and delay tumor progression in RPC. Therefore, we still expect larger and higher-quality RCTs to confirm the effectiveness of NAT.