Retroperitoneal Endometriosis: A Possible Cause of False Positive Finding at (18)F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography.

Endometriosis is a frequent and clinically relevant problem in young women. Laparoscopy is still the gold standard for the diagnosis of endometriosis, but frequently both morphologic and functional imaging techniques are involved in the diagnostic course before achieving a conclusive diagnosis. We present a case of a patient affected by infiltrating retroperitoneal endometriosis falsely interpreted as a malignant mass by contrast-enhanced magnetic resonance imaging and (18)F-fluorodeoxyglucose positron emission tomography/computed tomography.