Introduction: Even though endometriosis is relatively common among women of reproductive age, endometriosis of the appendix is rare. It has various clinical presentations and sometimes mimics appendicitis. Diagnosis is made from microscopic examination.
Case Description: Here, we report a case of a 42-year-old woman with severe right lower abdominal pain. An appendectomy was performed, and the tissue specimen was analyzed. Endometrial glands and stroma were found in the muscularis propria and serosa. The diagnosis of appendiceal endometriosis was established histologically.
Conclusion: Endometriosis of the appendix is a rare case. It can mimic appendicitis and is hard to detect preoperatively. A histopathology examination was recommended to confirm the diagnosis.