Impact of biliary stents on the diagnostic accuracy of EUS-guided fine-needle biopsy of solid pancreatic head lesions: A multicenter study

Background and Objectives: There is no clear evidence of a negative impact of biliary stents on the diagnostic yield of EUS-guided fine-needle biopsy (EUS-FNB) for diagnosing pancreatic head lesions. We aimed to evaluate the association between the presence of biliary stents and the diagnostic accuracy of EUS-FNB. Materials and Methods: A multicenter retrospective study including all jaundiced patients secondary to pancreatic head masses was performed. Patients were divided into two groups according to the presence of a biliary stent placed before EUS-FNB. Pathological results were classified according to the Papanicolaou classification and compared against the final diagnosis. Diagnostic measures in the two groups were compared. Multivariate logistic regression analyses including potential factors affecting EUS-FNB accuracy were performed. Results: Overall, 842 patients were included, 495 (58.8%) without and 347 (41.2%) with biliary stent. A plastic or a metal stent was placed in 217 (62.5%) and 130 (37.5%) cases, respectively. Diagnostic sensitivity and accuracy were significantly higher in patients without biliary stent than in those with stent (91.9% and 92.1% vs. 85.9% and 86.4%, P = 0.010 At multivariate analyses, lesion size (odds ratio [OR]: 1.05, 95% confidence interval [CI]: 1.02-1.09, P = 0.01) and presence of biliary stent (OR: 0.51, 95% CI: 0.32-0.89, P = 0.01) were independently associated with diagnostic accuracy. In the subgroup of patients with biliary stent, the type of stent (plastic vs. metal) did not impact EUS-FNB yield, whereas the use of larger bore needles enhanced diagnostic accuracy (OR: 2.29, 95% CI: 1.28-4.12, P = 0.005). Conclusions: In this large retrospective study, an indwelling biliary stent negatively impacted the diagnostic accuracy of EUS-FNB. Preferably, EUS-FNB should precede endoscopic retrograde cholangiopancreatography, especially in the case of small tumors.