Endometriosis of the Vermiform Appendix

Endometriosis of the appendix is usually asymptomatic and more commonly an incidental finding. When symptomatic, endometriosis may mimic acute appendicitis; the preoperative differentiation between the two may be impossible. We describe two patients who presented with signs and symptoms consistent with acute appendicitis but who, instead, were found to have endometriosis of the appendix. The histopathologic examination of the specimens demonstrated the presence of stroma, glands, and hemorrhage into the seromuscular layers of the appendix. This phenomenon is thought to be the etiology of the condition when mimicking acute appendicitis. The correlation between the presence of hemorrhage and the involvement of the seromuscular layers of the appendix, though not conclusive, is extremely good and substantiated in other reports.