The Sonographic Spectrum of Pathologically Proven Fibroadenoma of the Breast Among Women in Zaria, Northern Nigeria
Fibroadenoma is the commonest solid benign breast tumor of adolescents and young women. However, they vary in sonographic appearances from typical to atypical. It is imperative to be familiar with these features because significant overlap occurs between fibroadenoma and other breast masses, including breast cancer which has serious therapeutic consequences.
This study examined the different sonographic appearances of histologically confirmed breast fibroadenomas in Ahmadu Bello University Teaching Hospital, Zaria.
It was a cross-sectional review of the sonograms of one hundred and seven women with biopsy-proven fibroadenoma over a period of two years; and three women with sonographic mimics. A typical fibroadenoma is described as having a round, oval or lobulated shape, homogenous internal echotexture, well-circumscribed margin, parallel orientation to skin and posterior acoustic enhancement. The diagnostic criteria for atypical fibroadenoma were one or more of the following features: non-circumscribed margin, irregular shape, heterogeneous internal echo-pattern, posterior shadowing, microcalcification, and cysts >3mm. Data were recorded, edited and analysed using the Statistical package for social sciences version 20 (SPSS, Inc. Chicago Illinois, USA).
A total of 147 fibroadenomas were seen in 107 women whose mean age was 26.7 ± 8.34 years (range 13 to 53 years). The commonest presentation was a palpable mass. The predominant sonographic features were round (18.7%) or oval (69.2%) shape, a smooth or circumscribed contour (89.7%), hypo-echogenicity (72.9%), parallel orientation to the skin (85%) and posterior acoustic enhancement (83.2%). The features of atypical fibroadenomas were: irregular margins in 11.2%, heterogenous echotexture in 7.4%, cysts in 2.8% and posterior shadowing in 4.7%.
We conclude that most fibroadenomas in our series were typical. However, patients with atypical fibroadenoma, multiple lesions or a family history of breast cancer warrant surveillance because of increased risk of malignancy.
Keywords: Fibroadenoma, complex, breast, ultrasound