Feasibility of Endoscopic Ultrasound-Guided Tissue Acquisition for < 20-mm Upper Gastrointestinal Subepithelial Lesions.

Background: There are few reports on the usefulness of endoscopic ultrasound-guided tissue acquisition (EUS-TA) for upper gastrointestinal subepithelial lesions (SELs) < 20 mm with on-site stereomicroscopic assessment.

Objective: This study is aimed at investigating the usefulness of EUS-TA combined with on-site stereomicroscopic assessment using fine-needle biopsy (FNB) for SELs < 20 mm.

Methods: Participants (n = 133) underwent EUS-TA combined with on-site stereomicroscopic assessment using a 22-gauge FNB needle for upper gastrointestinal SELs between January 2018 and January 2022. We conducted a comparative study of diagnostic results after dividing the participants into two groups on the basis of lesion size: < 20 and ≥ 20 mm.

Results: There were 42 cases in the < 20-mm group and 91 cases in the ≥ 20-mm group. The diagnostic yield of EUS-TA in all cases was 97.7%, with values of 97.6% in the < 20-mm group and 97.8% in the ≥ 20-mm group and no significant difference between the groups. A total of 298 passes were made. The tissue sampling rate was 99.0%, and specimens with stereomicroscopically visible white cores (SVWCs) ≥ 4 mm were sampled at a rate of 87.2%. There was no significant difference in the sampling rate of specimens with SVWCs ≥ 4 mm between the groups. The diagnostic sensitivity in specimens with SVWC ≥ 4 mm was 98.5% (256/260 passes). Multivariate analysis showed that this factor significantly contributed to diagnosis (odds ratio 24.396, 95% confidence interval: 1.6596-4.7292, p < 0.001).

Conclusions: EUS-TA using a FNB needle combined with on-site stereomicroscopic assessment is a useful diagnostic method for < 20-mm SELs.