EUS-GUIDED DIAGNOSIS OF SUBEPITHELIAL GASTROINTESTINAL LESIONS: A MONOCENTRIC EXPERIENCE IN THE ERA OF THE NEW FNB NEEDLES

Aims Subepithelial lesions (SLs) are found in about 1% of all upper endoscopies; although the majority of them are benign, gastrointestinal stromal tumors (GISTs) have malignant potential and surgery is often needed. Diagnosis of GISTs relies on immunohistochemical staining (IHCS) and achieving adequate tissue from suspected GISTs by EUS-FNA/FNB remains a limitation. Aim of this study is to evaluate diagnostic yield of EUS+FNA/FNB in diagnosis of gastrointestinal SLs.

Methods We retrospectively analyzed patients underwent to EUS+FNA/FNB for gastrointestinal SLs in our academic center from January 2017 to October 2021. Demographic, clinical and histopathological data were analyzed from a prospectively collected database. Final diagnosis of the nature of SLs was based on surgical pathology when available or on specific IHCS.

Results Fifty-one patients were included, mostly female (53%) with a mean age of 69 years. SLs were located mostly in stomach (73%) and duodenum (18%); mean size of SLs was 32.4±14.6 mm.

FNA and FNB were performed respectively in 18 and 33 cases; in 2 cases EUS-sampling was inconclusive (1 FNA, 1 FNB), whereas in 49 cases (96%) final diagnosis was achieved (42 cases of GIST, 7 cases of leiomyoma). Feasibility of molecular biology analysis on FNA/FNB specimens was achieved in 68% of cases. In 18 out of 19 patients underwent to surgery FNB-based diagnosis was concordant with surgical pathology (95%).

Conclusions In our experience, EUS with FNA/FNB demonstrated high accuracy in diagnosis of gastrointestinal SLs, with 96% of cases correctly diagnosed and more than 2/3 of specimens suitable for molecular biology analysis.

Publication History

Article published online:
14 April 2022