Prospective, multicenter, observational study of tissue acquisition through EUS-guided fine-needle biopsy using a 25G Franseen needle.

Background: Recently, EUS-guided fine-needle biopsy (EUS-FNB) using a Franseen needle was developed for histological tissue acquisition. However, the yield of a 25G Franseen needle when acquiring histological core tissue has been unclear. Patients and Methods: We performed a prospective, multicenter, and observational cohort study that included 100 solid lesions scheduled for EUS-FNB using a 25G Franseen needle at eight centers in Hokkaido, Japan. Only EUS-FNB specimens acquired at the first pass were evaluated without a rapid on-site evaluation. The tissue acquisition rate, acquisition rate of an adequate specimen for histological assessment, the quality of tissue sample, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), diagnostic accuracy, and adverse events were evaluated. Results: We analyzed a total of 100 solid lesions in 100 patients. The patients were 57 males and 43 females with a median age of 70 years. The technical success rate was 100%. The tissue acquisition rate was 95.0%. The acquisition rate of an adequate specimen for histological assessment was 82.0%. The sensitivity, specificity, PPV, NPV, and diagnostic accuracy were 87.0%, 100%, 100%, 40.0%, and 88.0%, respectively. The adverse event rate was 1.0%, and it was reported in only one patient who had a moderate pancreatic fistula. Conclusions: EUS-FNB using the 25G Franseen needle was feasible, and adequate histological core tissue samples were acquired with this method.