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

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.