Subepithelial gastric tumours comprise a heterogeneous group of lesions. Endoscopic ultrasonography with fine-needle aspiration (EUS-FNA) is a useful approach but cannot always offer a definitive diagnosis to guide future therapeutic decisions. In the case we describe, biopsy samples of an antral subepithelial lesion and cytological analysis obtained with an EUS-FNA suggested the diagnosis of an adenocarcinoma. Endoscopic submucosal dissection (ESD) allowed en bloc resection of the tumour ensuring diagnosis and providing a definitive treatment.