EUS-FNAB for Solid Pancreatic Lesions: GIE | July 2026

Introduction:

Endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) is the standard technique for diagnosing solid pancreatic lesions. Traditionally, biopsy specimens are processed for cytology, often requiring on-site cytopathology support. This multicenter prospective study evaluated whether directly placing FNB tissue in formalin for histopathology could provide comparable diagnostic performance.

Why was this study needed?

• Many centers lack rapid on-site cytopathology (ROSE) or dedicated cytopathologists.
• Histopathology may better preserve tissue architecture for diagnosis and ancillary testing.
• The optimal processing method for EUS-FNB specimens remains uncertain.
• Simplifying specimen handling could improve workflow and reduce procedure time.
• Prospective data comparing histopathology with conventional cytology are limited.

Results:

• Histopathologic evaluation of EUS-FNB specimens achieved diagnostic accuracy comparable to conventional cytology for solid pancreatic lesions.
• Histopathology required fewer needle passes, potentially reducing procedure time and improving efficiency.
• With macroscopic on-site evaluation (MOSE), all histopathology specimens were adequate for analysis, supporting its reliability even without on-site cytopathologists.

Clinical Impact:

This study supports direct formalin submission of EUS-FNB specimens for histopathology as a practical alternative to cytology, particularly in centers without ROSE or cytopathology services. It may simplify specimen processing while maintaining excellent diagnostic performance.

Bottom Line:

Histopathology with MOSE is a reliable alternative to cytology for EUS-FNB of solid pancreatic lesions. It provides comparable diagnostic accuracy with fewer needle passes, making it an attractive approach for routine clinical practice, especially in resource-limited settings.