Extracellular vesicles in bile: a game changer in the diagnosis of indeterminate biliary stenoses?

Biliary stenoses are not infrequent clinical findings in various diseases or conditions. In some situations, differentiating the cause of biliary stenosis is difficult, and it often remains indeterminate. Indeterminate biliary stenoses can lead to repeated examinations, excess spending, and a delay in diagnosis and treatment. To date, the diagnosis of biliary stenosis has been based on histologic diagnosis through endoscopy. However, conventional brush cytology and intraductal biopsy via endoscopic retrograde cholangiopancreatography (ERCP) have low diagnostic sensitivity (1).