Repeated endoscopic ultrasound-guided fine-needle biopsy of solid pancreatic lesions after previous nondiagnostic or inconclusive sampling

Objectives: Repeated endoscopic ultrasound (EUS)-guided tissue acquisition represents the standard practice for solid pancreatic lesions after previous nondiagnostic or inconclusive results. Since data are lacking, we aimed to evaluate the diagnostic performance of repeated EUS fine-needle biopsy (rEUS-FNB) in this setting. The primary outcome was diagnostic accuracy; sample adequacy, sensitivity, specificity, and safety were secondary outcomes. Methods: Consecutive patients undergoing rEUS-FNB for solid pancreatic lesions at 23 Italian centers from 2019 to 2021 were retrieved. Pathology on the surgical specimen, malignant histology together with ≥6-month follow-up, and benign pathology together with ≥12-month follow-up were adopted as gold standards. Results: Among 462 patients, 56.5% were male, with a median age of 68 (59-75) years, malignancy prevalence 77.0%. Tumor size was 26 (20-35) mm. Second-generation FNB needles were used in 89.6% cases. Diagnostic accuracy, sensitivity, and specificity of rEUS-FNB were 89.2%, 91.4%, and 81.7%, respectively (19 false-negative and 12 false-positive results). On multivariate analysis, rEUS-FNB performed at high-volume centers (odds ratio [OR] 2.12; 95% confidence interval [CI] 1.10-3.17; P = 0.03) and tumor size (OR 1.03; 95% CI 1.00-1.06; P = 0.05) were independently related to diagnostic accuracy. Sample adequacy was 94.2%. Use of second-generation FNB needles (OR 5.42; 95% CI 2.30-12.77; P < 0.001) and tumor size >23 mm (OR 3.04; 95% CI 1.31-7.06; P = 0.009) were independently related to sample adequacy. Conclusion: Repeated EUS-FNB allowed optimal diagnostic performance after nondiagnostic or inconclusive results. Patients' referral to high-volume centers improved diagnostic accuracy. The use of second-generation FNB needles significantly improved sample adequacy over standard EUS-FNB needles.