Contrast-enhanced harmonic versus standard endoscopic ultrasound-guided fine-needle aspiration in solid pancreatic lesions: a single-center prospective randomized trial

Background Contrast-enhanced harmonic endoscopic ultrasound (CH-EUS) can visualize necrotic areas and vessels inside lesions. CH-EUS findings combined with EUS-guided fine-needle aspiration (EUS-FNA) improves diagnosis in pancreatic solid masses. CH-EUS can also guide EUS-FNA (CH-EUS-FNA), potentially improving the diagnostic rate of EUS-FNA, but such superiority has not been proved in prospective studies. We aimed to assess whether CH-EUS-FNA is superior to standard EUS-FNA for specific diagnosis of solid pancreatic masses and what factors affect the diagnostic rate. Methods This randomized controlled study in one tertiary medical academic center included patients with suspected pancreatic solid masses on transabdominal ultrasound or computed tomography (CT) scan. Two passes with a 22-G standard FNA needle were done using EUS-FNA and CH-EUS-FNA in random order, and the visible core obtained was sent for histological analysis. Final diagnosis was based on EUS-FNA or surgical specimen results and on 12-month follow-up by imaging. Results 148 patients were evaluated. EUS-FNA and CH-EUS-FNA showed diagnostic sensitivities of 85.5% and 87.6%, respectively (not significantly different) and the combined sensitivity of the two passes was 93.8 %. The false-negative rate was not significantly different when hypoenhanced or hyperenhanced lesions were compared with the EUS-FNA results. No differences were seen for the results related to location, size, tumor stage, chronic pancreatitis features, or presence of biliary plastic stent. Conclusions The diagnostic rates for samples obtained using 22-G needles with standard EUS-FNA and CH-EUS-FNA were not statistically significantly different.