title: Leiomyomas beyond the uterus: unusual locations, rare manifestations.
abstract: Uterine leiomyomas affect 20%-30% of women older than 35 years. Extrauterine leiomyomas are rarer, and they present a greater diagnostic challenge: These histologically benign tumors, which originate from smooth muscle cells, usually arise in the genitourinary tract (in the vulva, ovaries, urethra, and urinary bladder) but may arise in nearly any anatomic site. In addition, unusual growth patterns may be seen, including benign metastasizing leiomyoma, disseminated peritoneal leiomyomatosis, intravenous leiomyomatosis, parasitic leiomyoma, and retroperitoneal growth. In the presence of such a pattern, a synchronous uterine leiomyoma or a previous hysterectomy for removal of a primary uterine tumor may be indicative of the diagnosis. However, some extrauterine leiomyomas may mimic malignancies, and serious diagnostic errors may result. The most useful modalities for detecting extrauterine leiomyomas are ultrasonography, computed tomography, and magnetic resonance (MR) imaging. The superb contrast resolution and multiplanar capabilities of MR imaging make it particularly valuable for characterizing these tumors, which usually show low signal intensity similar to that of smooth muscle on T2-weighted images. The radiologist's recognition of this and other characteristic features may help steer the clinician toward timely, appropriate management and away from unnecessary, potentially harmful treatment.
authors.affiliation: Department of Diagnostic Imaging, Ottawa Hospital, Ottawa, ON, Canada. nfasih@ottawahospital.on.ca
authors.forename: Najla
authors.initials: N
authors.lastname: Fasih
authors.forename: Alampady K
authors.initials: AK
authors.lastname: Prasad Shanbhogue
authors.forename: David B
authors.initials: DB
authors.lastname: Macdonald
authors.forename: Margaret A
authors.initials: MA
authors.lastname: Fraser-Hill
authors.forename: Demetrios
authors.initials: D
authors.lastname: Papadatos
authors.forename: Ania Z
authors.initials: AZ
authors.lastname: Kielar
authors.forename: Geoffrey P
authors.initials: GP
authors.lastname: Doherty
authors.forename: Cynthia
authors.initials: C
authors.lastname: Walsh
authors.forename: Matthew
authors.initials: M
authors.lastname: McInnes
authors.forename: Mostafa
authors.initials: M
authors.lastname: Atri
mesh_terms: D000328:Adult; D003952:Diagnostic Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007889:Leiomyoma / Q000175:diagnosis*; D008875:Middle Aged; D010534:Peritoneal Neoplasms / Q000175:diagnosis*; D035583:Rare Diseases / Q000175:diagnosis; D014594:Uterine Neoplasms / Q000175:diagnosis