Abstract
Vermiform appendiceal cancers are rare and commonly diagnosed incidentally after appendectomy for acute appendicitis. Establishing a diagnosis and staging appendiceal cancer is important as the treatment options differ based on the subtypes of tumor and their spread in the peritoneum. The role of endosonography in tissue diagnosis of appendiceal cancer is limited. Most cases are diagnosed and staged radiologically and surgically. Tissue diagnosis is key in management, especially when diagnosis is unclear by other modalities. We report a case of transduodenal endoscopic ultrasound-guided biopsy of an appendiceal lesion, which had significant impact on patient outcome.