BACKGROUND
Mucinous cystadenoma is a benign cystic tumor lined by mucinous gastrointestinal-type epithelium. This entity usually presents as a large multicystic mass containing mucus and fluid, predominantly in women aged 20 to 40 years. Mucinous ovarian tumors frequently manifest as large unilateral pelvic masses. Differential diagnoses include non-neoplastic conditions such as follicular cysts, corpus luteum cysts, and endometriosis. Giant ovarian tumors are rare; symptoms often result from the large size of the mass and may include pain, abdominal or pelvic fullness, and a palpable mass. We describe the incremental value of contrast-enhanced multiparametric magnetic resonance imaging (MRI) for identifying and characterizing a giant multilocular adnexal lesion in a young woman.
CASE REPORT
An 18-year-old woman was referred to our emergency department for a giant multilocular pelvic mass incidentally discovered on transvaginal ultrasound; she presented with severe abdominal pain. Contrast-enhanced multiparametric MRI supported the adnexal origin of the mass and favored a benign diagnosis based on the absence of mural nodules, solid components, septal contrast enhancement, or restricted diffusion on diffusion-weighted images. MRI thus provided a preoperative assessment favoring a benign lesion, whereas histopathological examination confirmed the final diagnosis of benign ovarian mucinous cystadenoma.
CONCLUSIONS
This case highlights the incremental value and supporting role of contrast-enhanced multiparametric MRI when evaluating a giant pelvic mass in a young patient. MRI confirmed the origin, precisely localized the mass, and facilitated appropriate preoperative surgical planning; the definitive diagnosis was established by histopathological examination.

Keywords: Magnetic Resonance Imaging; Ovarian Cysts