Abstract
A 58-year-old man was admitted to our hospital complaining of lower abdominal pain. Abdominal CT revealed a swollen appendix and inflammation of the adjacent fat tissues. We made the diagnosis of acute appendicitis and performed emergency operation. Intraoperatively, the vermiform appendix was inflamed and swollen with pus, therefore, we performed appendectomy. We could not detect any evident mass in the vermiform appendix during the operation. Gross examination of the resected specimen revealed a 14-mm elevated lesion and a thick appendix wall, with erosion and ulceration of the mucosal surface. Histopathological examination of the elevated lesion showed proliferating spindle cells with nuclear palisading. Immunohistochemical analysis showed positive staining for S-100 protein and negative staining for desmin, c-kit and CD34. Based on the findings, we made the diagnosis of appendiceal schwannoma. Herein, we report a rare case of appendiceal schwannoma, which was diagnosed incidentally at appendectomy.
