The efficacy of neoadjuvant therapy (NT) versus surgery first (SF) for pancreatic ductal adenocarcinoma (PDAC) remains controversial. A random-effects meta-analysis of only prospective randomized controlled trials (RCTs) comparing NT versus SF for potentially resectable (PR) or borderline resectable (BR) PDAC was performed. Among six RCTs including 850 patients, 411 (48.3%) received NT and 439 (51.6%) SF. In all included trials, NT was gemcitabine-based: four using chemoradiation and two chemotherapy alone. Based on an intention-to-treat analysis, NT resulted in improved overall survival (OS) compared to SF (HR 0.73, 95% CI 0.61-0.86). This effect was independent of anatomic classification (PR: hazard ratio (HR) 0.73, 95% CI 0.59-0.91; BR: HR 0.51 95% CI 0.28-0.93) or NT type (chemoradiation: HR 0.77, 95% CI 0.61-0.98; chemotherapy alone: HR 0.68, 95% CI 0.54-0.87). Overall resection rate was similar (risk ratio (RR) 0.93, 95% CI 0.82-1.04, I2 = 39.0%) but NT increased the likelihood of a margin-negative (R0) resection (RR 1.51, 95% CI 1.18-1.93, I2 = 0%) and having negative lymph nodes (RR 2.07, 95% CI 1.47-2.91, I2 = 12.3%). In this meta-analysis of prospective RCTs, NT significantly improved OS in an intention-to-treat fashion, compared with SF for localized PDAC. Randomized controlled trials using contemporary multi-agent chemotherapy will be needed to confirm these findings and to define the optimal NT regimen.
Keywords: chemotherapy; folfirinox; pancreas cancer; pancreatectomy; pancreatic cancer; preoperative therapy; radiation therapy.