and unusual histopathologic findings. Results: A total of 2757 appendectomies were performed to treat patients with suspected acute appendicitis. The mean age of patients was 25.4 ± 11.8 years (range, 5-86) and 69.7% were male. There were 1608 suppurative appendicitis (58.3%), 855 appendix vermiform (31%), 99 gangrenous appendicitis (3.6%), 19 perforated appendicitis (0.7%), 19 phlegmonous appendicitis (0.7%), and 157 patients with unusual histopathologic findings (5.7%). The unusual histopathologic findings (n = 157) were contained fibrous obliterated appendix (80.2%), carcinoid tumor (7%), mucocele (3.8%), Enterobius vermicularis (3.8%), B-cell non-Hodgkin's lymphoma (B-NHL) (1.9%), eosinophilic infiltration (1.2%), and granulomatous infiltration (1.9%). Histopathologic findings of appendectomy specimens revealed 14 malignancies among 157 unusual findings (8.9%; 0.5% of all appendectomies) including carcinoid tumor (n = 11) and B-NHL (n = 3). Conclusions: Although unusual pathologic findings in appendectomy specimens are rare, histopathologic assessment will allow early diagnosis of many unusual diseases. Thus, even when the macroscopic appearance of appendectomy specimens is normal, all specimens should be subjected for routine histopathologic examination.