A Prospective, Randomised Controlled Trial Investigating the Diagnostic Sensitivity of Contrast‐Enhanced Harmonic Endoscopic Ultrasound-Guided Versus Conventional Endoscopic Ultrasound‐Guided Fine-Needle Aspiration/Biopsy for Solid Pancreatic Lesions

Abstract

Background: Contrast‐enhanced harmonic endoscopic ultrasound (CEH‐EUS) is useful in the differential diagnosis of solid pancreatic lesions (SPLs). This study aimed to investigate the usefulness of CEH‐EUS-guided fine-needle aspiration/biopsy (FNA/B), without on-site cytopathology. Methods: This randomised controlled trial was conducted at two university hospitals in Korea. Patients with SPLs were prospectively enrolled and randomly assigned (1:1) using a table of random sampling numbers, to two parallel groups, the interventional group (CEH-EUS) or the control group (conventional EUS). The investigators, endoscopists, patients, and pathologists were unmasked to the group assigned. The diagnostic sensitivity and optimal number of needle passes for pathologic diagnosis were investigated and compared between groups. Clinical trial number: KCT0001840. Findings: In total, 252 patients with SPLs were screened and 240 were enrolled from March 2016 to September 2019, with 120 patients assigned to each group. Pancreatic malignancies and neuroendocrine tumours were found in 202 (90·83%) and nine (3·75%) patients, respectively. There was no statistically significant difference between the groups in terms of age, sex, lesion size (30·96±12·09 mm in the CEH-EUS group vs 33·09±16·39 mm in the conventional EUS group; p=0·252), location, adverse event rate (2·5% vs 2·5%; p=0·999), and disease distribution (malignancy, neuroendocrine tumour, and benign masses, p=0·395). The diagnostic sensitivity values in the CEH-EUS and conventional EUS groups were 85·8% and 88·3%, respectively (p=0·564). All the patients in the conventional EUS group and most of those in the CEH-EUS group received a pathological diagnosis within three needle passes. Interpretation: This prospective, randomised trial showed that the diagnostic sensitivity for SPLs was not different between the CEH‐EUS and conventional EUS groups, and there were no independent factors that could improve diagnostic sensitivity. CEH-EUS-guided FNA/B will not need to be used routinely for the diagnosis of SPLs. CEH-EUS may be selectively considered in small, indeterminate lesion. Trial Registration: (Clinical trial registration at https://cris.nih.go.kr/cris; KCT0001840) Funding Statement: None. Declaration of Interests: There are no conflicts of interest to declare. Ethics Approval Statement: This study was approved by the Institutional Review Board (GAIRB2016-026) and conducted in accordance with the principles set forth in the Declaration of Helsinki. Written informed consent was obtained from all patients.