Preoperative image of the mucinous cystadenoma. (A) Computed tomography revealed a tumor (arrows). I, coronal imaging; II, sagittal imaging; III, axial imaging. (B) Ultrasonography showed distension of the appendix (arrow) that did not compress; the lack of increased Doppler flow in the wall supported a noninflammatory diagnosis. (C) Colonoscopy: submucosal tumor-like elevations of the appendiceal orifice (arrow).