Management of appendiceal neuroendocrine tumors in the light of new guidelines

Appendiceal neuroendocrine tumors (ANETs) are the most common in the appendix, detected in histopathological appendectomy specimens, which are resected for acute appendicitis. If tumor detection does not show signs of metastatic disease or obvious features of carcinoid syndrome, preoperative diagnosis remains a challenge. However, the treatment and follow-up algorithm change over time. In our study, we aimed to present 10 years of diagnostic and management experience.

A retrospective study of all patients who underwent emergency appendectomy, with the intention to treat clinically acute appendicitis at Bakirkoy Dr. Sadi Konuk Hospital (Istanbul, Turkey), was undertaken. Patients with diagnoses other than ANETs were excluded. Age, gender, preoperative clinical findings, operative procedure, and histopathological results identified as ANETs were evaluated.

ANETs were detected in 24 patients (0.42%) in the histopathological examination of 5720 appendectomy specimens between December 2011 and October 2020. Mean age of patients was 30 years, with 58.3% female. The majority were located at the tip of appendix (62.5%). Eleven patients (45.83%) were graded as T1, one patient (4.16%) as T2, 11 (41.83%) as T3, and one patient (4.16%) as T4. Secondary hemicolectomy was performed in four patients. Median postoperative follow-up was 43 (17-108) months.

In addition, ANETs are rare and largely detected by chance; therefore, precise examination of routine appendectomy specimens is essential for diagnosis. Accurate tumor staging, in light of new algorithms, has an important place in follow-up and treatment management.