Mayumi Takeuchi1, Kenji Matsuzaki1, Masafumi Harada1
1Department of Radiology, University of Tokushima, Tokushima, Japan
We evaluated MR manifestations including DWI of 11 ovarian thecomas/fibrothecomas and compared with those of 12 non-thecomatous benign tumors and 51 primary malignant ovarian tumors. All thecomas/fibrothecomas showed totally or partially low intensity on T2-weighted images and high intensity on DWI, whereas none of non-thecomatous benign tumors show high intensity on DWI, and only one of 51 malignant tumors show partially low intensity on T2-weighted images. The ADC value (x 10-3 mm2/seconds) of thecomas/fibrothecomas (1.16 +/- 0.07) is significantly higher than that of malignant tumors (1.05 +/- 0.18) (p=0.01), and lower than that of benign tumors (1.44 +/- 0.24) (p=0.001).