EUS-FNB Shows High Diagnostic Yield in Autoimmune Pancreatitis: Study
Researchers have found in a new study that endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) demonstrated 79% diagnostic accuracy for autoimmune pancreatitis (AIP), with newer Franseen and Fork-tip needles outperforming older bevel-type needles. Adequate tissue samples were obtained in 97% of cases, and EUS-FNB enabled a definitive diagnosis in 69% of patients when other diagnostic tests were inconclusive. The study was published in the journal BMC Gastroenterology by Huiling Yu and colleagues.
In order to assess the usefulness of EUS-FNB in terms of its diagnostic accuracy, the yield of tissue, and safety profile, systematic searching was performed through databases such as PubMed, Embase, Cochrane Library, CNKI, and Wanfang database in order to find relevant diagnostic studies that had been conducted. For the final meta-analysis, a total of 16 published diagnostic studies which included one randomized controlled trial and four prospective cohort studies involving a total of 732 patients with suspected AIP were selected.
The statistical analysis for the assessment of pooled estimates in terms of diagnostic accuracy, adequacy of samples collected, clinical value in indeterminate diagnosis, and adverse events was performed using random-effects model.
Key findings:
- The overall pooled diagnostic accuracy for EUS-FNB in AIP was 79% (95% CI, 73%–83%), while the pooled sample adequacy rate reached 97% (95% CI, 95%–98%).
- Diagnostic accuracy varied significantly by needle design (P < 0.001), showing 90% accuracy for Fork-tip needles (95% CI, 80%–99%) and 83% for Franseen needles (95% CI, 75%–90%), both outperforming reverse/forward-bevel needles at 51% (95% CI, 31%–71%).
- The 22G needle size demonstrated statistically superior diagnostic accuracy (P < 0.001) at 85% (95% CI, 79%–91%) compared to larger 19G/20G needles at 70% (95% CI, 42%–98%).
- EUS-FNB successfully established a definitive diagnosis in 69% (95% CI, 50%–88%) of patients where cross-sectional imaging, IgG4 serology, or extrapancreatic organ involvement failed to yield a diagnosis.
- The overall procedure-related adverse event rate remained remarkably low at 4% (95% CI, 1%–8%).
Therefore, the EUS-FNB technique proves to be a highly efficient, safe, and precise diagnostic tool used for obtaining histological material in suspected cases of autoimmune pancreatitis. The efficiency of this method is proved by its diagnostic accuracy of 79% and involvement in making diagnosis clear in 69% of cases. Using the 22G Franseen or Fork-Tip needles is the best solution for endosonographers while dealing with complicated cases of pancreatic diseases.
Reference:
Yu, H., Kou, J., He, Q. et al. The diagnostic yield of endoscopic ultrasound-guided fine-needle biopsy in autoimmune pancreatitis: a systematic review and meta-analysis. BMC Gastroenterol 26, 477 (2026). https://doi.org/10.1186/s12876-026-05164-y
