This is an open access article under the CC BY 4.0 license (https://creativecommons.org/licenses/by/4.0/). Signa Vitae 2021 vol.17(1), 75-78 ©2021 The Authors. Published by MRE Press. http://www.signavitae.com/ Submitted: 15 July, 2020 Accepted: 24 August, 2020 Published: 08 January, 2021 DOI:10.22514/sv.2020.16.0093 ORIGINAL RESEARCH Incidental appendiceal neoplasias: ten years' experience with 1,642 patients Server Sezgin Uludag 1, * , Nazim Gures 2 , Abdullah Kagan Zengin 1 1 Istanbul University-Cerrahpasa, Cerrahpasa Faculty of Medicine, Department of General Surgery, İstanbul, Turkey 2 Balikesir Atatürk City Hospital, Department of General Surgery, İstanbul, Turkey *Correspondence sszgn.uludag@gmail.com (Server Sezgin Uludag) Abstract Background: Acute appendicitis is the most common surgical emergency. In this study, we investigated the rate of neoplasia among patients who underwent an appendectomy in our center, a large Tertiary Care Teaching Hospital. Methods: We retrospectively reviewed 1,642 cases of appendectomies performed between 2007 and 2017. In this study, the data included demographic data, operative and pathological findings, and additional procedures following the appendectomy. Results: Of the 1,642 appendectomies, 1,294 were laparoscopic, and 348 were open procedures. Appendiceal neoplasia was encountered in the examination of appendix specimens taken from 20 patients. Sessile serrated adenoma (SSRA) was found in seven patients, neuroendocrine tumor (NET) in six patients, low-grade mucinous neoplasia (LGMN) in four patients, mucinous cystadenoma (MCA) in two patients, and diffuse adenoma (DA) in one patient. Two patients underwent right hemicolectomy due to positive surgical margins from previous surgeries. Colonoscopy and computed tomography (CT) control were performed on all neoplasia patients during the postoperative period, and no additional pathology was seen. Conclusions: Although the probability of neoplasia after appendectomy is low, it should be considered. Adenomas and neuroendocrine tumors seem to be the most common neoplasias that are incidentally encountered in appendectomy specimens. Keywords Acute appendicitis; Appendiceal neoplasia; Sessile serrated adenoma; Neuroendocrine tumor 1. Introduction Acute appendicitis is the inflammation of the appendix, and the appendix is an essential organ since it is considered the most common emergency surgical pathology worldwide [1]. The pathogenesis of appendicitis is still not fully understood. Mul- tiple factors, such as mechanical, infectious and genetic issues, may cause inflammation of the appendix [2]. Appendicitis may be simple or complicated. The simple form does not cause inflammation to surrounding tissues, while in complex ap- pendicitis, inflammation may lead to gangrene or perforation, with or without the development of an abscess. Perforation occurs in 13-20% of patients presenting with acute appendicitis [3]. Apart from open and standard laparoscopic approaches, single-incision laparoscopic surgery and the natural orifice transluminal endoscopic surgery (NOTES) procedures are the surgical techniques used in the treatment of acute appendicitis [4]. Appendiceal neoplasias, classified as mucinous and non- mucinous, are found in appendix specimens with rates of 0.9- 1.4%, and the incidence rates are increasing [5]. Thus, in this 1,642-case series, we sought to determine the rate of appendiceal neoplasia and the types of neoplasia that were seen in appendectomy specimens. 2. Methods We retrospectively reviewed 1,642 cases of appendectomies performed between 2007 and 2017. The present study included patients over 18 years of age who underwent appendectomy with a preliminary diagnosis of appendicitis. Patients with incidental appendix neoplasias were studied. The male/female ratios and open-laparoscopic procedure rates were determined. The demographic characteristics and pathological findings of 20 cases of appendiceal neoplasia were revealed. Additional follow-up and interventions were also reviewed for these 20 patients. 3. Results Of the 1,642 reviewed patients, 553 were women and 1,089 were men. Moreover, 1,294 of the cases were performed laparoscopically and 348 cases of appendectomy were per- formed using open surgery (Table 1).