Imaging Features and Pathologic Characteristics of Ovarian Thecoma

OBJECTIVE: To analyze the imaging findings of ovarian thecoma and to better understand the tumor features based on aspect of computed tomography and magnetic resonance images. METHODS: Nineteen ovarian thecomas confirmed by histopathologic examination were analyzed retrospectively. Image characteristics were analyzed and compared with those of the pathologic features. RESULTS: The mean diameter of tumors was 9.6 cm. The masses were well defined (n = 17) or ill defined (n = 2) and appeared solid with cystic areas (n = 11), entirely solid (n = 4), or cystic with solid components (n = 4). On T2-weighted/spectral adiabatic inversion recovery (T2WI/SPAIR) images, 12 cases appeared isointense or slightly hyperintense. Of the 12 cases, 8 had patchy hypersignal areas. On computed tomographic images, 7 cases showed hypodensity or isodensity. All tumors exhibited mild enhancement. On pathologic examination, the tumor was composed of spindle cells with a moderate amount of cytoplasm. CONCLUSION: Imaging manifestations of ovarian thecoma are various and nonspecific. However, a large, well-defined mildly enhanced solid mass with cystic areas and especially isointense or slightly hyperintense on T2WI/SPAIR sequence in pelvic cavity may suggest the diagnosis of ovarian thecoma.