Randomized Controlled Study Comparing Endoscopic Ultrasonography Guided Fine Needle Aspiration Using Free Stylet 22g and 25 g Needles in Solid Lesions

This is a randomized controlled study comparing EUS-FNA with 22 gauge and 25 gauge needles in consecutive patients.

Summary

Background: three needle sizes for endoscopic ultrasonography guided fine needle aspiration (EUS-FNA) are currently available: 22 Gauge (G), 25 G and 19 G. However, well design studies comparing them regarding efficacy and feasibility are lacking.

Aims: to investigate diagnostic yield, specimen adequacy, feasibility and complications of the conventional 22 G compared with the 25 G needle.

Methods: patients ≥ 18 years, referred to EUS-FNA for a solid lesion will be considered for inclusion. Patients with suspected diagnosis of lymphoma, GIST, sarcoidosis, significant coagulopathy (APT < 50% or platelets < 50000/mm3), use of warfarin or other anticoagulants, use of clopidogrel within 7 days of EUS, inability or refusal to sign the informed consent and pregnancy or suspected pregnancy will be excluded.

Participants will be randomized to 22 G needle and 25 G FNA. Chi-square test will be used to compare proportions. Continuous variables will be compared using Student´s t test. A two-tailed P values of less than 0.05 will be considered statistically significant. The diagnostic yield of 25 G and 22 G needle will be evaluated by four criteria: sensitivity, specificity, positive predictive value and negative predictive value. An expected rate of 85% diagnostic yield from EUS guided FNA by using 22G needle will be considered. By using a power of 80% and an α value of 0.05 would be necessary 120 patients per group to detect a 15% difference in the rate of diagnostic yield.