Imaging in gynecological disease (5): clinical and ultrasound characteristics in fibroma and fibrothecoma of the ovary.
OBJECTIVES
To describe the clinical and ultrasound features of fibroma and fibrothecoma of the ovary.


METHODS
Sixty-eight women with a histological diagnosis of fibroma or fibrothecoma of the ovary who had undergone a preoperative ultrasound examination between 1999 and 2007 were identified from the databases of four ultrasound centers. The tumors were characterized on the basis of ultrasound images, ultrasound reports and research protocols (when applicable) using the terms and definitions of the International Ovarian Tumor Analysis (IOTA) group. In 51 patients, ultrasound information had been collected prospectively; in the remaining 17 cases it was retrieved retrospectively from ultrasound reports and images. In 44 cases, electronic ultrasound images of good quality were available. These were reviewed by two observers, who described them using pattern recognition.


RESULTS
Of the 68 patients identified, 53 had fibroma and 15 had fibrothecoma. The mean patient age was 54 (range, 17-80) years. Sixty-three percent (41/65) were postmenopausal and 60% (39/65) had no symptoms. Most (75%; 51/68) fibromas/fibrothecomas were solid tumors and most (75%; 51/68) manifested minimal or moderate blood flow on color Doppler examination. Using pattern recognition, all solid fibromas/fibrothecomas were described as round, oval or slightly lobulated tumors. Most (66%; 29/44) were solid tumors, with regular or slightly irregular internal echogenicity with stripy shadows, and some contained cystic spaces. Others (23%, 10/44) were solid tumors with regular or slightly irregular internal echogenicity without stripy shadows and with or without cystic spaces. Two were solid tumors that were so dense it was difficult to assess their internal echogenicity, two were multilocular solid tumors with large cystic spaces and one was described as being mainly cystic. Half of the women with fibroma/fibrothecoma had fluid in the pouch of Douglas and 16% (11/68) had ascites; CA 125 titers > or =35 U/mL were found in 34% (17/50) of the cases in which CA 125 results were available.


CONCLUSIONS
Most fibromas and fibrothecomas are round, oval or lobulated solid tumors that cast stripy shadows and are associated with fluid in the pouch of Douglas, and most manifest minimal to moderate vascularization. A fibroma/fibrothecoma with atypical ultrasound appearance may be mistaken for a malignancy, in particular if associated with fluid in the pouch of Douglas or ascites, high color content and raised CA 125 levels.