Abstract: "Background: Neuroendocrine tumours (NETs) are well-differentiated epithelial neoplasms with morphological and immunohistochemical features of neuroendocrine differentiation. Case Description: We report a 22-year-old woman with lower right abdominal pain. Patient underwent appendectomy and the specimen was sent for histopathological examination. On macroscopic examination, we received tissue originating from mass in the appendix, showed mass was brownish gray and irregular. The size was approximately 4 cm. On cut section, tumor mass appeared at apical of the appendix, 0.5 cm from the end of resection margin. "