Endoscopic ultrasound (EUS) guided fine needle aspiration (EUS-FNA) is the primary technique for tissue acquisition for pancreatic lesions. Despite widespread adoption of the techniques, the diagnostic yield of EUS-FNA for pancreatic lesion is highly variable, with sensitivities ranging from 64-95%, specificities ranging from 75-100% and overall diagnostic accuracy ranging from 78-95%.
Despite its mainstay as the primary technique for tissue acquisition, EUS-FNA has several limitations. The standard EUS-FNA does not routinely provide core biopsy specimen with preserved tissue architecture, which is required for immunohistochemical staining and for definitive diagnosis of conditions, such as lymphoma, gastrointestinal stromal tumors, Immunoglobulin G (IgG)-4-associated lymphoplasmacytic sclerosing pancreatitis. Furthermore, the diagnostic yield of EUS-FNA is highly dependent on the availability of bedside cytotechnologist or cytopathologist for rapid onsite evaluation (ROSE), which increases the overall cost required to perform EUS-FNA.
Recently, multiple dedicated EUS fine needle biopsy (FNB) needles have been developed to obtain core specimens. Early small studies have shown promising results with these EUS-FNB needles.
The objective of this paired cohort study is to evaluate the diagnostic accuracy of EUS-FNA with ROSE compared to EUS-FNA with ROSE. Participants will be assigned to the arms. If EUS-FNB without ROSE is shown to be non-inferior to the current standard of care of EUS-FNA with ROSE in pancreatic lesions, this study has the potential to make EUS-guided tissue acquisition more economical (with elimination for the need for cytopathology staff onsite) as well as provide core histological specimen without sacrificing the overall diagnostic yield.
