Hiromichi Tsunashima

BACKGROUND: Endoscopic ultrasound-guided tissue acquisition (EUS-TA) is essential technique for sampling solid pancreatic lesions. However, the optimal needle type for achieving high histological diagnostic capability remains unclear. This study compares the histological diagnostic capabilities of the 19G FNA needle and the 22G FNB needle for solid pancreatic lesions. METHODS: This single-center, retrospective study was conducted in patients who underwent EUS-TA for solid pancreatic lesions. Patients were allocated to either Group A, utilizing the 19G FNA needle, or Group B, utilizing the 22G FNB needle. The primary outcome was the diagnostic accuracy based on histology alone. RESULTS: 143 patients were analyzed, with 61 in Group A and 82 in Group B. Diagnostic accuracy was significantly higher in Group B for both histology alone (85.4% vs. 68.9%, p=0.02) and overall diagnostic accuracy (85.4% vs. 73.8%, p=0.02). Logistic regression analysis revealed that lesion size ≥25 mm was an independent factor contributing to higher diagnostic accuracy (OR 3.32, 95% CI 1.28-8.64, p=0.01). Subgroup analysis showed that diagnostic accuracy for 15–25 mm lesions was significantly higher in Group B (90.0% vs. 63.2%, p=0.02). Additionally, trans-gastric punctures had higher accuracy in Group B (94.7% vs. 73.5%, p=0.01). CONCLUSIONS: Our study showed the overall superiority of the 22G FNB needle for EUS-TA of solid pancreatic lesions. However, 19G FNA needle remains a valuable option under specific conditions.