A Case of Appendiceal Adenocarcinoma with Neuroendocrine Differentiation Diagnosed After Laparoscopic Appendectomy for Acute Appendicitis

Abstract

We report a case of appendiceal adenocarcinoma with neuroendocrine differentiation that was diagnosed post-appendectomy. A 34-year-old woman with right lower abdominal pain and nausea was referred to our hospital. Abdominal CT revealed a swollen appendix, with the dirty fat sign around the appendix. A diagnosis of appendicitis was made, and laparoscopic appendectomy was performed. Although macroscopic examination of the resected specimen revealed no tumors, histopathology revealed appendiceal adenocarcinoma with neuroendocrine differentiation showing invasion of the muscularis propria at the appendiceal apex. Therefore, the patient underwent further laparoscopic cecum resection with lymph node dissection. No evidence of recurrence has been detected until date, one year since the surgery. Careful examination, for any tumors, of the resected appendiceal specimens after appendectomy is important, even for young patients.