Ovarian cystadenofibromas: characteristic magnetic resonance findings with pathologic correlation.

Ovarian cystadenofibroma is a benign tumor and may appear as a multilocular cystic mass with solid nodular components mimicking malignant ovarian tumor. Preoperative diagnosis is required to avoid excess surgical procedure. We report characteristic magnetic resonance imaging (MRI) findings of 2 cases with pathologic correlation. On T2-weighted images, the solid components of the tumors showed very low intensity, in which very high intense tiny cysts were present reflecting dense fibrous stromal proliferation with scattered small cystic glandular structures. This "black sponge"-like appearance was considered to be diagnostic.