Extended Versus Standard Lymphadenectomy for Pancreatic Head Cancer: Meta-Analysis of Randomized Controlled Trials

The evidence for improved prognostic assessment and long-term survival for extended pancreatoduodenectomy (EPD) compared to standard pancreatoduodenectomy (SPD) in patients with carcinoma of the head of the pancreas has not been considered from only randomized controlled trials (RCTs).

The aim of this study was to conduct a systematic review and meta-analysis of the outcomes comparing SPD and EPD in RCTs. Searches were performed on MEDLINE, Embase and Cochrane databases using MeSH keyword combinations: 'pancreatic cancer', 'pancreaticoduodenectomy', 'extended', 'randomized' and 'lymphadenectomy'. RCTs published up to 2014 were included. Overall post-operative survival, morbidity, 30-day mortality and length of hospital stay were the outcomes assessed.

Five eligible RCTs with 546 participants were included (EPD = 276 and SPD = 270). EPD was associated with a significantly higher number of excised lymph nodes (LNs) compared to SPD (mean difference = 15.73, 95% confidence interval (CI) = 9.41-22.04; P < 0.00001; I(2) = 88%). LN metastasis was detected in 58-68 and 55-70% of patients who had EPD and SPD, respectively. EPD did not improve overall survival (hazard ratio (HR) = 0.88, 95% CI = 0.75-1.03; P = 0.11) but did worsen post-operative morbidity compared to SPD (risk ratio (RR) = 1.23; 95% CI = 1.01-1.50; P = 0.004; I(2) = 9%). There were no differences in the 30-day mortality (RR = 0.81; 95% CI = 0.32-2.06; P = 0.66; I(2) = 0%) or length of hospital stay (mean difference = 1.39, 95% CI = -2.31 to 5.09; P = 0.46; I(2) = 67%).

SPD is associated with reduced morbidity, but equivalent long-term benefits compared to patients undergoing EPD.