Elastography and Contrast-Guided Sampling Using Endoscopic Ultrasound-Guided Fine-Needle Biopsy for Evaluation of Large Gastric Subepithelial Lesions: A Case Report

Endoscopic ultrasound (EUS) with fine-needle biopsy (FNB) is one of the techniques applied for sampling subepithelial lesions (SELs) of the gastrointestinal tract. Elastography and contrast-enhanced evaluation could permit identification of different patterns among areas of the lesions, depending on their consistence and the presence of vital cells or necrosis. Targeting a specific area when performing FNB in the case of large lesions could potentially permit an increase in accuracy and reduce the need for re-sampling. A 61-year-old woman was admitted reporting severe abdominal pain. The patient underwent cholecystectomy many years ago. She had no known family history of gastrointestinal, hepatic, biliary, or pancreatic disease. Laboratory tests were normal. A computed tomography scan showed a large lesion between the stomach and the pancreatic body, suspected to originate from the gastric wall. An endoscopic view showed a large bulging into the gastric lumen and EUS identified a lesion originating from the muscular layer of the gastric wall. Elastography and contrast-enhanced EUS identified two different areas, one softer with lower enhancement (A) and the other harder with higher enhancement after contrast injection (B). FNB was performed targeting both the areas, sending samples for separate histological evaluation. Histology showed a gastrointestinal stromal tumor (GIST), finding differences in amount of necrotic and neoplastic cells between the two areas. EUS-FNB guided by elastography and/or contrast-enhanced EUS could identify differences within large SELs, allowing targeting of areas more likely to collect diagnostic samples.