Characterization of Ovarian Granulosa Cell Tumors using Magnetic Resonance Imaging

PURPOSE: To identify the MRI features that aid in the characterization of ovarian granulosa cell tumors. MATERIALS AND METHODS: 11 MR pelvis of an adult woman with pathology-proven ovarian granulosa cell tumors with surgical pathology. We evaluated the patient’s age, Ca-125, size, laterality, and with MRI features such as indirect signs (i.e., thickened endometrium > 0.9 cm), morphology (cystic, solid-cystic, or solid), subacute hemorrhage, T2 signal (low or intermediate-to-high), restricted diffusion (B values: 0, 50, 1000 sec/mm3/ADC), and dynamic enhancement (intense or similar to myometrium). Also, the presence of ascites, peritoneal implants, or adenopathy. RESULTS: The final cohort included 11 women with a surgical-pathological diagnosis of granulosa cell tumors. The median age was 52.4 years (range, 17–80). The Ca-125 level was with a median within normal limits. The median size was 9.4 cm. Most cases were unilateral (81.8%) and more frequent on the left (54.5%). MRI ANALYSIS: 36.4% had endometrial thickening. Ovarian granulosa cell tumors were polymorphous: cystic (54.6%), mixed solid-cystic (9.1%), and solid (36.3%). Most GC had intermediate to high signal on T2 (90.9%), restricted diffusion (81.8%), intense enhancement (81.8%), and 36.4% had intraparenchymal bleeding. 9.1% had associated implants/adenopathy/ascites at diagnosis. CONCLUSION: The MRI features characteristic of ovarian granulosa cell tumors were the polymorphous morphology, an intense enhancement to the myometrium, restricted diffusion, and the presence of intraparenchymal hemorrhage.