A Case of Low–grade Appendiceal Mucinous Neoplasm That Was Diagnosed by Histopathology

Abstract

A 47–year–old woman with a history of lower right abdominal pain and fever was admitted to our hospital. Physical examination revealed slight tenderness of the right flank. In addition to slight increases of the inflammatory reactants detected on blood examination, abdominal contrast–enhanced computed tomography (CT) revealed an enlarged appendix and surrounding panniculitis, based on which we made the diagnosis of acute appendicitis. The patient was referred to our department and emergency laparoscopic appendectomy was performed. The histopathological diagnosis was low–grade appendiceal mucinous neoplasm (LAMN). LAMNs are clinically malignant tumors that can cause pseudomyxoma peritonei. There are no therapeutic guidelines for LAMNs. We report a case of LAMN in which no cystic lesions could be identified on CT and preoperative diagnosis was difficult; we present the case with a review of the relevant literature.