Appendiceal mucinous cystadenoma intussuscepted into the cecum on a patient with rectal carcinoma: a case report.

Appendiceal mucinous cystadenoma intussusception is rare but is readily ruptured and may form pseudomyxoma peritonei [1–3]. This condition is difficult to diagnose preoperatively due to its similarity to appendicitis or to atypical symptoms. A computed tomography (CT) scan, radioscopy, or colonoscopy can differentiate appendiceal mucinous cystadenoma intussusception from a cecal polyp or mass [4, 5]. Misdiagnosis may lead to treatment with false-polypectomy colonoscopy, which can result in appendiceal perforation and mucinous cystadenoma rupture. Etiologies include anatomical variations of the appendix and pathological conditions [6]. Especially in patients with rectal cancer, pseudomyxoma peritonei is difficult to detect.