Ovarian Fibromas: MR Imaging Findings with Emphasis on Intratumoral Cyst Formation

Purpose: The purpose of this study was to assess MR imaging findings of ovarian fibromas with emphasis on intratumoral cyst formation.

Materials And Methods: MR images with a 1.5-T unit obtained in 17 consecutive patients (age range, 18-87 years; mean age, 58 years) with 17 histologically proven ovarian fibromas were retrospectively reviewed for the size, configuration, signal intensity of solid components, and presence of cystic degeneration and edema within tumor. Size, number, and location of intratumoral cysts were also assessed.

Results: The maximum diameter of tumors ranged from 3.3 to 19.1cm (mean, 10.9 cm). Seven (41%) tumors were multinodular. On T2-weighted images, solid components of tumors were heterogeneously mixed hypo- and hyperintensity in 16 (94%) tumors. Nine (53%) tumors demonstrated cysts and 16 (94%) demonstrated edema within tumor. The maximum diameter of the largest cysts ranged from 1.0 to 13.2 cm (mean, 6.4 cm), and the number of cysts per tumor ranged from 1 to 60 (mean, 15.6). Of the nine tumors with cystic formation, the predominant location of the cysts was peripheral in five (56%), exophytic in two (22%), central (11%) in one, and diffuse in one (11%).

Conclusion: Peripheral or exophytic cyst formation may be characteristic MR imaging features with ovarian fibromas.