Incidental Appendiceal Neuroendocrine Tumor Post Appendectomy: Surgery Is Here to Stay.

Abstract

Neuroendocrine tumors (NETs) arising from the appendix are rare neoplasms but carry significant consequences if missed. These malignancies are typically diagnosed after an appendectomy via histopathological evaluation of the appendix. This aspect further solidifies surgery's place in the treatment of appendicitis. A 25-year-old female patient presented to the emergency department with a three-day history of right-sided abdominal pain associated with nausea and two episodes of non-bilious vomiting. Physical examination was initially benign but later showed tenderness to the right of the umbilicus. A CT scan revealed an inflamed appendix. Based on clinical and radiological findings, the diagnosis of acute appendicitis was made. The patient underwent a laparoscopic appendectomy. Histopathological analysis of the appendix was performed, identifying an appendiceal neuroendocrine tumor (aNET). Following the initial diagnosis, an appropriate workup was conducted, which included a colonoscopy, computed tomography (CT) scan, and further biopsies. Histopathological analysis of the appendix revealed a well-differentiated grade 1 NET, measuring 3.5 cm, with invasion into peri-appendiceal tissues. Further evaluation through a repeat CT scan and colonoscopy revealed inflammation in the rectum, cecum, and right colon. Furthermore, a subsequent laparoscopic right hemicolectomy was performed. Pathology of the hemicolectomy specimen revealed no residual NET, though lymph node involvement was present, with three out of 18 nodes testing positive for lymphatic spread. This case report highlights the diagnostic and management challenges associated with aNETs, emphasizing the importance of surgical intervention in the context of acute appendicitis. The discovery of aNETs can significantly alter the clinical management course, as it did for this patient, who required further surgical intervention and ongoing surveillance. The timely identification and removal of the tumor likely improved the patient's prognosis.