Background and aim: Previous studies comparing endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) results with different gauge needles have all been carried out with the stylet in place and show no clear advantage to the larger 22-G needle. Similar data for stylet-free EUS-FNA (SF-EUS-FNA) are unavailable. The aim of the present study was to determine whether diagnostic yield and specimen adequacy is superior with the 22-G needle as compared to the 25-G needle.
Methods: All patients ≥ 18 years referred for solid-lesion EUS-FNA were eligible. Patients with suspected diagnosis of lymphoma, gastrointestinal stromal tumor, sarcoidosis, significant coagulopathy (international normalized ratio > 1.5 or platelets < 50000/mm(3)), use of clopidogrel within 7 days of EUS, and pregnancy were excluded. The two needles were compared regarding diagnostic yield, sample adequacy, bloodiness, ease of puncture, visibility, number of passes, failures, and complications.
Results: One hundred and twenty consecutive patients were included and 126 lesions were sampled. Sensitivity, specificity, positive predictive value and negative predictive value for the 22-G SF-EUS-FNA were 83%, 100%, 100% and 56%, respectively, and for the 25-G SF-EUS-FNA were 88.8%, 100%, 100% and 76.5%, respectively (P=NS). There were no significant differences between the 22-G and the 25-G FNA needles in sample adequacy, bloodiness, ease of puncture, FNA failure, visibility, number of passes and complications; and no significant differences between either needle were found in relation to lesion site.
Conclusion: For SF-EUS-FNA, the larger 22-G needle offers no advantage over the smaller 25-G needle.