Describe the unusual locations and rare manifestations of genital smooth muscle tumors. Recognize the MR imaging findings useful to guide the diagnosis and management.

Leiomyomas are benign smooth muscle tumors (SMT) and are the most common among mesenchymal tumors in the female genital tract. They occur most commonly in the uterus but may be found wherever there is smooth muscle. SMT of male genital tract are very uncommon neoplasms. MR imaging is the most accurate imaging technique for detection, localization, and characterization of these tumors, which usually show a low signal intensity similar to that of smooth muscle on T2-weighted images. However, benign SMT may pose considerable diagnostic problems...

LEIOMYOMAS OF FEMALE GENITAL TRACT Leiomyomas constitute the most common benign uterine tumors (20–30% of reproductive age females). Clinical presentation Most patients are asymptomatic. Symptoms are related to the number, size, and location of the tumors. Due to their hormonal sensitivity, they shrink in menopause and occasionally may grow and bleed in patients receiving progestational therapy or who are pregnant. Typical appearance Location within the myometrium of the uterine corpus (FIGO classification). FIGO0-FIGO8 (Fig. 1): submucosal, intramural, subserosal and others. Subserosal and submucosal tumors may...

Knowledge of the complete spectrum of MR imaging features characteristic of genital smooth muscle tumors, including their more unusual manifestations and atypical locations are important because imaging plays a crucial role in diagnosis and appropriate management.

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