2020 Volume 53 Issue 1 Pages 46-53
An 80-year-old woman presented with several days’ history of right lower abdominal pain. Her CT scan showed thickening of the wall of the appendix and the ileocecum. Biopsy confirmed the diagnosis of a poorly differentiated adenocarcinoma of the appendix, and ileocecal resection was performed. Macroscopically, the tumor was observed to arise from the appendix. Histopathological analysis revealed the invasion of large atypical cells which were positive for synaptophysin and chromogranin A by immunohistochemical staining. Since the Ki-67 index was 70%, the lesion was diagnosed as a primary neuroendocrine carcinoma of the appendix. Although the postoperative course was uneventful, she developed liver metastasis and pleural dissemination only 2 months after the operation. Moreover, her general condition gradually got worse and she died 5 months postoperatively. Neuroendocrine carcinomas have an aggressive clinical course and are associated with poor prognosis. Here, we report a rare case of primary neuroendocrine carcinoma of the appendix.
