Management and Long-Term Follow-up Outcomes of Appendiceal Neuroendocrine Tumor Patients: Evaluation of Single-Center Data

Aim: Appendiceal neuroendocrine tumors (NETs) are rare NET that are often incidentally discovered following appendectomy performed for acute appendicitis.Herein, we report our institution's experience regarding the management and long-term follow-up of appendiceal NETs.Method: This study included patients who underwent appendectomy for acute appendicitis and were diagnosed with appendiceal NETs between 2011 and 2020.Patient data were retrospectively retrieved from the hospital computer system.Clinical information, demographic details, tumor size, localization within the appendix, histopathological findings, and surgical procedures were evaluated. Results:The study included data from 44 patients, with 22 men and 22 women, and a mean age of 31.112.7 years.All patients presented with symptoms consistent with acute appendicitis upon admission to the hospital.Tumors were distally located in 33 patients, centrally located in seven patients, and proximally located in four patients.Among the 44 patients included in the study, 42 underwent appendectomy, whereas two underwent primary right hemicolectomy during the initial surgery.One patient who underwent appendectomy required subsequent right hemicolectomy 3 weeks later.The mean follow-up duration was 5.42.5 years.During the follow-up period, metastasis was detected in only one patient with a tumor size larger than 2 cm located proximally.No recurrence or evidence of metastasis was observed in the remaining patients during long-term follow-up. Conclusion:According to the results of this study, appendectomy may be sufficient for appendiceal NETs measuring <1 cm, and routine follow-up may not be necessary.For appendiceal NETs measuring 1-2 cm in diameter, further studies are needed to establish treatment protocols.