Objective: Aimed to investigate the incidence of neuroendocrine tumors (NET) in the appendectomy specimens of the patients who underwent appendectomy for various indications.
Methods: 2252 cases, that were performed appendectomy at Harran University Faculty of Medicine and examined histopathologically in Pathology department between January 2004 and May 2014, were analyzed retrospectively.
Results: In the study, it was reported NET in only 3 (0.13%) of these patients. All of the patients with NET were women and mean age ± SD was 58,33 ± 18.14 years. All of the patients had been operated for acute appendicitis and the tumor was detected incidentally during microscopic examination. The tumor was localized to the distal portion of the appendix in all cases, the tumor sizes were 1.4cm, 1cm, 0.7cm (mean: 1,03 ± 0,35), respectively. Although, muscular layer and periappendicular fatty tissue involvement was present in each case, cellular atypia was minimal. Mitotic activity was calculated as 1-2 in 10 high power field. Immunohistochemical staining was performed in all cases and tumor cells showed positive staining with pancytokeratin, synaptophysin and chromogranin in all. Ki-67 proliferative indices were found 1-2%. In all cases, the presence of acute appendicitis had been reported in the peritumoral appendix.
Conclusion: On histopathological examination of the excised appendiceal materials, NET should be constantly kept in mind in differential diagnosis and should be evaluated by an appropriate sampling.