An ovarian fibroma is a benign ovarian tumour of sex cord - stromal (mesenchymal) origin. Although fibromas account for approximately 4% 2-3 of all ovarian neoplasms they are the most common sex cord ovarian tumour.
Fibromas occur at all ages but are most frequently seen in middle-aged women.
Fibromas are generally asymptomatic and are often detected at palpation during routine gynaecologic examination. Tumours can reach a large size at presentation.
The tumour belongs to the same histopathologic spectrum as an ovarian thecoma / ovarian fibrothecoma. It is composed of spindle cells forming variable amounts of collagen. Sectioning of a fibroma typically reveals a chalky-white surface that has a whorled appearance, similar to that of a uterine fibroid. Areas of oedema, occasionally with cyst formation, are also relatively common.
- Meigs syndrome - consists of an ovarian fibroma with ascites and a pleural effusion.
- fibromas are seen in 75% of patients with nevoid basal cell carcinoma syndrome 1.
On ultrasound, fibromas most commonly manifest as solid, hypo-echoic masses with sound attenuation. As such, they may appear similar to (or difficult to distinguish from) a pedunculated subserosal uterine fibroid.
However, the sonographic appearance can be variable and some tumours can rarely have cystic components.
Fibromas usually manifest as diffuse, slightly hypoattenuating masses with poor, very slow contrast enhancement. calcification and bilaterality are both uncommon.
Signal characteristics include
- T1 - fibromas usually demonstrate homogeneous, relatively low signal intensity
- fibromas appear as well-circumscribed masses with low signal intensity containing scattered high-signal-intensity areas representing oedema or cystic degeneration.
- a band of T2 hypointensity separating the tumour from the uterus on all imaging planes is also considered a characteristic feature.
- T1 C+ (Gd) - usually shows heterogenous enhancement 5
Treatment and prognosis
Ovarian fibromas are almost always benign 3.
General imaging differential considerations include
- large pedunculated subserosal uterine leiomyoma
- 1. Fonseca RB, Grzeszczak EF. Case 128: Bilateral ovarian fibromas in nevoid basal cell carcinoma syndrome. Radiology. 2008;246 (1): 318-21. doi:10.1148/radiol.2461041824 - Pubmed citation
- 2. Jeong YY, Outwater EK, Kang HK. Imaging evaluation of ovarian masses. Radiographics. 20 (5): 1445-70. Radiographics (full text) - Pubmed citation
- 3. Atri M, Nazarnia S, Bret PM et-al. Endovaginal sonographic appearance of benign ovarian masses. Radiographics. 1994;14 (4): 747-60. Radiographics (abstract) - Pubmed citation
- 4. Outwater EK, Wagner BJ, Mannion C et-al. Sex cord-stromal and steroid cell tumors of the ovary. Radiographics. 18 (6): 1523-46. Radiographics (abstract) - Pubmed citation
- 5. Eurorad teaching files : Case 1209
Synonyms & Alternative Spellings
|Synonyms or Alternative Spelling||Include in Listings?|
|Fibroma of the ovary||✗|
|Fibroma of ovary||✗|