Diagnostic accuracy and Patient Derived Organoid (PDO) yield of 19G vs 22G Franseen needles for EUS-Guided biopsy in solid pancreatic lesions: A prospective comparative study.

[BACKGROUND/OBJECTIVES] Endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) is the standard procedure for conducting histological assessment of solid pancreatic lesions and obtaining tissue cores for generating patient-derived organoids (PDOs) in unresectable patients. The aim of this single-institution, prospective, comparative study was to investigate whether the use of the larger 19-gauge (G) FNB needle improves diagnostic performance and PDO establishment rate compared to the 22G FNB needle.

[METHODS] Patients with suspected solid pancreatic lesions on imaging were prospectively recruited between April 2019 and April 2022. Diagnostic EUS-FNB was performed with both needles in every patient. The primary endpoint was the diagnostic accuracy of the samples and the secondary endpoint the rate of successful PDO generation for which additional samples were obtained with both needles in a subset of twenty patients with high probability for pancreatic cancer.

[RESULTS] Of the 119 enrolled patients, eighty-five patients underwent EUS-FNB with both needle sizes. The overall diagnostic accuracy and the sensitivity for malignancy were similar for both needles. The sensitivity for pancreatic ductal adenocarcinoma (PDAC) was 83.3 % for the 22G and 76.7 % for the 19G needle (p = .46). Of the 20 patients with PDO sampling, 10 PDOs were established from 19G samples, 11 from 22G samples and 8 from both needle sizes (p = .99). The overall PDO success rate, regardless of needle size, was 60 %.

[CONCLUSIONS] Compared to 22G, the 19G- FNB needle did not provide higher diagnostic accuracy or PDO yield, suggesting no need for larger needle sizes for PDO generation.