Forward-viewing echoendoscope versus standard echoendoscope for endoscopic ultrasound-guided tissue acquisition of solid lesions: a randomized, multicenter study

 BACKGROUND:  A forward-viewing linear (FVL) echoendoscope has been developed with the aim of overcoming some of the limitations of standard curved linear-array (CLA) echoendoscopes. There are no existing studies comparing the performance of the two echoendoscopes for endoscopic ultrasound-guided tissue acquisition (EUS-TA) of solid lesions other than subepithelial lesions. METHODS:  This was a prospective, multicenter, randomized trial with a noninferiority design comparing FVL vs. CLA echoendoscopes in patients with solid lesions of the gastrointestinal tract or adjacent organs. Primary outcomes were successful identification of the lesion and success of EUS-TA. Secondary outcomes were safety, sensitivity, specificity, and diagnostic accuracy of the two different scopes for EUS-TA. RESULTS:  126 patients with solid lesions were randomly assigned to the CLA group (63 patients) or the FVL group (63 patients). The two groups were homogeneous with no differences in terms of needle type used, mean number of passes, and site of EUS-TA. No differences were observed between the FVL vs. CLA scopes in identification of the lesion (96.8 % vs. 98.4 %; P > 0.99) and technical success of EUS-TA (92.1 % vs. 96.8 %; P = 0.44). No adverse events occurred. Overall, diagnostic accuracy (77.8 % vs. 84.1 %), sensitivity (76.6 % vs. 84.1 %), and specificity (81.3 % vs. 84.2 %) did not differ between the two groups. CONCLUSIONS:  Our results strongly suggest that the FVL echoendoscope is noninferior to the CLA scope for the detection and performance of EUS-TA in patients with solid lesions of the gastrointestinal tract and adjacent organs. In addition, the FVL scope has the same diagnostic yield, accuracy, and safety as the CLA scope.