Low diagnostic yield of transduodenal endoscopic ultrasound-guided fine needle biopsy using the 19-gauge Flex needle:...

Previous limited experiences have reported the 19-gauge flexible needle to be highly effective in performing endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) for transduodenal lesions. We designed a large multicenter prospective study with the aim at evaluating the performance of this newly developed needle.

Consecutive patients with solid lesions who needed to undergo EUS sampling from the duodenum were enrolled in 6 tertiary care referral centers. Puncture of the lesion was performed with the 19-gauge flexible needle (Expect™ and Slimline Expect™ 19 Flex). The feasibility, procurement yield, and diagnostic accuracy were evaluated.

Totally, 246 patients (144 males, mean age 65.1 ± 12.7 years) with solid lesions (203 cases) or enlarged lymph nodes (43 cases) were enrolled, with a mean size of 32.6 ± 12.2 mm. The procedure was technically feasible in 228 patients, with an overall procurement yield of 76.8%. Two centers had suboptimal procurement yields (66.7% and 64.2%). Major complications occurred in six cases: two of bleeding, two of mild acute pancreatitis, one perforation requiring surgery, and one duodenal hematoma. Considering malignant versus nonmalignant disease, the sensitivity, specificity, positive/negative likelihood ratios, and diagnostic accuracy were 70.7% (95% confidence interval [CI]: 64.3-76.6), 100% (95% CI: 79.6-100), 35.3 (95% CI: 2.3-549.8)/0.3 (95% CI: 0.2-0.4), and 73.6% (95% CI: 67.6-79). On multivariate analysis, the only determinant of successful EUS-FNB was the center in which the procedure was performed.

Our results suggest that the use of the 19-gauge flexible needle cannot be widely advocated and its implementation should receive local validation after careful evaluation of both the technical success rates and diagnostic yield.