Pelvic mass: Role of imaging in the diagnosis and management

The differential diagnosis of a pelvic mass found on clinical examination or on an imaging study varies depending on the age and menstrual status of the patient and the clinical presentation. The most commonly encountered pelvic mass in the gynecological patient arises from the uterus, fallopian tubes, or the ovaries. The most common cause of a pelvic mass is of uterine origin, a leiomyoma being the most common underlying cause of the uterine enlargement. The imaging features and the differential diagnostic considerations in diagnosing uterine, adnexal, and non-ovarian masses are described. Less common causes of pelvic masses include those arising from the gastrointestinal tract. Ultrasonography is the modality of choice in the initial assessment of a pelvic mass and often the only modality that is needed to arrive at an accurate diagnosis and consequently for appropriate management of the pelvic mass. A final section of the chapter describes the imaging differential diagnosis of pelvic masses with a focus on the supplemental role of magnetic resonance imaging (MRI) and computed tomography (CT) in characterizing the nature of the pelvic mass. The current role of CT and MRI in the staging of gynecological malignancies is also presented.