Most occur in adult women, with ~66% in postmenopausal women. Although they account for ~1% of all ovarian tumors , they are the most common benign solid ovarian tumor. It represents <2% of pediatric ovarian tumors.
The thecoma component of a fibrothecoma can secrete estrogen, and the patient may present with abnormal vaginal bleeding and endometrial hyperplasia.
They may be seen as a homogeneous hypoechoic mass with posterior acoustic shadowing, although in most cases the sonographic appearance is nonspecific.
The vast majority (~80%) of ovarian fibrothecomas appear as solid masses with a delayed accumulation of contrast medium. On dynamic CT, there is an absence of arterial vessels and absence or slight early uptake of contrast enhancement . Calcification may be present and, as these tumors enlarge, myxoid or cystic degeneration may occur, resulting in a heterogeneous pattern .
Reported signal characteristics include :
- T1: typically shows homogeneous low signal intensity
- lesions show predominantly homogeneous low signal intensity (from fibrous components)
- scattered high signal areas may be present representing areas of cystic degeneration +/- edema
Treatment and prognosis
Most cases are benign and surgical resection is curative.