Acute Appendicitis Revealing a Neuroendocrine Tumor: A Case Report

Appendiceal neuroendocrine tumors (ANETs) rarely are first-hand diagnoses made after appendectomy for suspected acute appendicitis. We present the case of a 27-year-old man with classical signs of appendicitis. The histopathological report showed that it was a well-differentiated (G1) neuroendocrine tumor of 7 mm in size with no invasive features. Further immunohistochemistry was carried out to confirm the diagnosis (chromogranin-A+, CD56+, Ki-67 <1%). No further treatment was needed. After three years of clinical follow-up, there is neither recurrence nor metastasis. The taken case underlines the importance of systematic histological analysis and an excellent prognosis of small, non-invasive ANETs.