Endoscopic ultrasound-guided sampling of gastrointestinal subepithelial lesions: just wet it

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is the main method for acquisition of tissue from gastrointestinal subepithelial lesions (SELs). Despite the development of new needles, diagnostic yield remains low. A new method of aspiration has been described, where the needle is filled with saline [wet-suction technique (WST)], with promising results in pancreatic lesions. This method has not been tested in SELs.

Prospective single center study to assess the diagnostic yield of EUS-FNA+WST in the diagnosis of SELs, without the use of rapid on-site evaluation. In mesenchymal tumors, the diagnosis was considered positive only when immunohistochemistry could differentiate between gastrointestinal stromal tumor and leiomyoma.

Eighty-seven patients with SELs were included (55% male, mean age 66 years). Mean SEL size was 25 mm (min 10 mm, max 120 mm), mean number of passes was 3 (±0.8). A 22G needle was used in 72 patients (83%), 19G in 10 (12%) and 25G in 5 (6%). We obtained a conclusive cytopathological diagnosis in 74 cases (diagnostic yield of 85%) and immunohistochemistry was performed in 70 cases (81%). The most frequent diagnoses were gastrointestinal stromal tumor (n = 34, 37%), leiomyoma (n = 13, 15%) and metastases (n = 10, 11%).

Wet suction technique allowed an excellent diagnostic yield in the EUS-guided evaluation of SELs. We suggest that, after proper replication of these results, WST may become the first-line method in the management of these lesions.