Appendiceal neuroendocrine neoplasms and resection of the mesoappendix: a retrospective comparative study

Incidental appendiceal neoplasms are identified in approximately 1% of the specimens of suspected appendicitis. The current institutional policy is to perform en bloc mesoappendix resection during routine laparoscopic appendicectomy allowing for staging, reducing the need for oncological right hemicolectomy (ORH). Herein, we review en bloc mesoappendicectomy in clinical practice and its effects on the rate of ORH.

We reviewed all cases of appendicectomy performed at the Auckland City Hospital between 1 May 2014 and 31 May 2019. Clinical notes and histopathological reports were reviewed. All neoplasms, surgical techniques and the need for further surgery were analysed.

A total of 2455 appendicectomies were performed with an approximately similar number of procedures between the sexes and an overall median age of 31 years. Overall, 86% (n = 2098) of the specimens included resection of the mesoappendix, and 58 (2.4%) appendiceal neoplasms were identified. Of them, 33 (1.3%) specimens included neuroendocrine appendiceal neoplasms. Eleven (33%) patients with appendiceal neuroendocrine neoplasms were recommended ORH. One of these patients may have avoided additional surgery, whereas 3 (9.1%) patients with tumours of 10-20 mm avoided ORH because their mesoappendix was resected.

At our centre, there has been a significant change in the practice of mesoappendix resection, and we support resection of the mesoappendix during appendicectomy. The procedure is technically straightforward and safe, incurs no increases in costs or time, allows for accurate tumour staging and guides decisions regarding further surgical interventions.