Role of EUS and EUS-guided FNA in the diagnosis of symptomatic rectosigmoid endometriosis

Background: Rectosigmoid endometriosis is an underrecognized cause of GI symptoms in women. Pelvic magnetic resonance imaging and CT have a low sensitivity in making this diagnosis. The role of EUS and EUS-guided FNA (EUS-FNA) in the diagnosis of rectosigmoid endometriosis in symptomatic patients is not well studied. Methods: A review of medical records identified 5 women who were diagnosed with rectosigmoid endometriosis by EUS and EUS-FNA over a period of 1 year. Observations: Five women with nonspecific GI complaints underwent EUS examination of a rectosigmoid subepithelial mass found on colonoscopy EUS revealed a hypoechoic lesion infiltrating the muscularis propria and the serosa of the rectal wall, and extending outside the rectal wall, findings consistent with rectosigmoid endometriosis. This diagnosis was confirmed by EUS-FNA, surgical exploration, and/or the patient's clinical course. Conclusions: EUS and EUS-FNA are noninvasive, sensitive techniques for the diagnosis of rectosigmoid endometriosis in symptomatic patients.