Appendiceal Nodules in the Setting of Endometriosis Can Be Carcinoid Tumors.

Background: Endometriosis is occasionally found in the appendix, particularly in severe forms of deep infiltrating disease. Carcinoid tumor is the most common neoplasm of the appendix and may be overlooked or misdiagnosed when there are multiple endometriosis lesions in the pelvis.

Methods: We describe two cases of carcinoid tumor diagnosed in patients who underwent surgery to treat endometriosis, in whom the diagnosis of appendiceal endometriosis was presumed.

Conclusions: In the context of endometriosis, surgery is indicated when the appendix is affected. Despite the more likely diagnosis of appendiceal endometriosis, carcinoid tumors cannot be ruled out by imaging examinations.