Ovarian fibroma

Fibromas are composed mostly of fibroblasts and spindle cells and abundant collagen contents. Fibromas are not hormonally active. Fifteen percent of fibromas are associated with ascites (Fig. 9.32), and in 1% pleural fluid is also found [83]. This triad of an ovarian fibroma, ascites and pleural effusion constitutes the benign Meigs syndrome, which can be associated with elevated Ca-125 levels [84]. In basal cell nevus syndrome, numerous basal cell carcinomas are associated with abnormalities of bones, eyes, brain, and tumors, including ovarian bilateral fibromas [85]. 

Fig. 9.33a,b. Ovarian fibroma in CT. Transaxial pelvic CT at the uterine level (a) and above (b) in a 55-year-old woman with abdominal fullness. A large lesion (asterisk) is found in the mid pelvis above the level of the uterus and bladder (b). It is well demarcated and displays a slightly inhomogeneous solid structure. Contrast enhancement is distinctly less than that of the myometrium (arrow). No calcifications were found throughout the lesion. Minimal ascites was seen. Histopathology revealed a 9-cm fibroid of the left ovary... 

The solid morphology and the signal characteristics of fibromas and fibrothecomas are fairly characteristic. Pedunculated uterine fibroids and fibroids of the broad ligaments can display similar imaging characteristics. The latter can only be differentiated from ovarian fibromas or fibrothecomas when they are separated from the ovary. Subserosal pedunculated fibroids can be discrimi-... 

Cutwater EK, Siegelman ES, Talerman A et al (1997) Ovarian fibromas and cystadenofibromas MRI features of the fibrous component. J Magn Reson Imaging 7 465-71... 

Tumors derived from the sex cords or ovarian mesenchyme compose 5% to 12% of all ovarian neo-plasms. 413 Benign tumors in the fibroma-thecoma group are relatively common. Other sex cord-stromal tumors and mesenchymal tumors are rare. The most common malignant sex cord- stromal tumor is granulosa cell tumor, which composes 1% of 2% of all malignant ovarian tumors. There are two types of granulosa cell tumors an adult type that occurs mainly in postmenopausal... 

Fibromas and fibrothecomas are solid ovarian tumors accounting for 3%-4% of all ovarian tumors and 10% of solid adnexal masses. They are typically unilateral (90%), and occur in peri- and postmenopausal age women. 

Differential diagnosis includes solid ovarian tumors in younger age, e.g., granulosa cell tumors and teratomas. In MRI, uterine fibroma and fibrothecoma may display a similar appearance on T2-weighted images however, contrast enhancement in these tumors is less and delayed. Especially in CT, differentiation of subserosal uterine fibroids from solid dysgerminomas is not possible. 

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