The Impact of Endoscopic Ultrasound Adoption on Etiological Shifts in Biliary Obstruction: A 15-Year Real-World Study

Background and ObjectivesThe etiology of biliary obstruction has undergone notable shifts over recent decades, yet long-term epidemiological studies addressing these changes remain scarce. With the widespread clinical adoption of endoscopic ultrasound (EUS), its role in altering diagnostic patterns warrants investigation. This study aimed to characterize the evolving disease patterns of biliary obstruction and specifically evaluate the impact of EUS adoption on driving these perceived etiological shifts over a 15-year period. MethodsThis retrospective, single-center study analyzed data from patients with biliary obstruction over a 15-year period. Time-series analysis was employed to characterize evolving disease patterns. To investigate the drivers underlying the observed trends, we applied a difference-in-differences (DID) analytical framework, uniquely treating the widespread clinical adoption of EUS as a natural experiment. Furthermore, multivariable logistic regression was utilized to identify independent predictors for malignant biliary obstruction of pancreatic origin. ResultsAmong 5,672 patients with pathological diagnoses, the disease spectrum shifted significantly toward malignant etiologies, particularly pancreatic and ampullary cancers, over the study period. The DID analysis confirmed that the broad adoption of EUS was associated with a significant relative increase in the precise diagnosis of malignancies detectable by this modality. Multivariable analysis further identified the EUS promotion era and calendar year as independent predictors for the pancreatic origin of malignancy. ConclusionsThe observed increase in pancreatic and ampullary cancers among patients with biliary obstruction is significantly associated with the enhanced diagnostic capabilities brought by EUS. This suggests that the diagnostic evolution driven by the widespread adoption of EUS, alongside potential epidemiological changes, is a major contributing factor to the perceived etiological shifts in biliary obstruction.