Assessment of the technical performance of the flexible 19-gauge EUS-FNA needle

Background A needle made of nitinol has been developed with enhanced flexibility to overcome the limitations of the currently available 19-G EUS-FNA needles. Objective Evaluate the ability to perform transduodenal FNAs, procure histologic specimens, and undertake therapeutic interventions using the flexible 19-G needle. Design Prospective cohort study. Setting Tertiary-care academic medical center. Patients Consecutive patients with subepithelial masses, pancreatic head or uncinate lesions, or lesions adjacent to the pancreatic head, and patients undergoing therapeutic intervention. Interventions Perform tissue acquisition and interventions with the flexible 19-G FNA needle. Main Outcome Measures Evaluate the ability to perform transduodenal passes with the flexible 19-G FNA needle. Also, assess the utility of the needle to yield both cytologic and histologic samples and to perform therapeutic interventions. Results Of the 50 patients enrolled, tissue acquisition was undertaken in 38 and therapeutic intervention in 12. Of 38 patients from whom tissue was procured, 32 tissue samples were from pancreatic head/uncinate or peripancreatic masses and 6 were from subepithelial masses. Tissue acquisition, which included transduodenal passes, was successful and adequate for cytologic assessment in all 38 patients (100%). Satisfactory histologic specimens were procured from 36 of 38 (94.7%) patients. An onsite diagnosis was established in 35 of 38 (92.1%) patients. In 3 patients with indeterminate/suspicious lesions, a definitive diagnosis was established at histology. A mean of 1.45 ± 0.79 passes per patient was performed. All 12 therapeutic interventions were successful (100%) and included pseudocyst drainage in 5, pelvic abscess drainage in 2, fiducial placement in 2, celiac plexus neurolysis in 2, and cholangiogram in 1. Needle dysfunction or procedural complications were not encountered. Limitations Single-center study with limited power. Conclusions Preliminary data suggest that the flexible 19-G needle can be used for procuring cytologic aspirates and histologic specimens and to undertake therapeutic interventions even by the transduodenal route. Confirmatory studies are required in a larger cohort of patients with varied pathologic conditions to validate these findings.