Definition of Fibroadenosis (Fibrocystic Breast Disease)
Fibroadenosis, also known as fibrocystic breast disease or fibrocystic changes, is a benign breast condition classified as a nonproliferative lesion characterized by adenosis, fibrosis, and cyst formation in the breast tissue. 1
Pathophysiologic Characteristics
- The condition results from estrogen predominance and progesterone deficiency, leading to hyperproliferation of connective tissue (fibrosis) followed by epithelial proliferation 2
- Fibrocystic changes are believed to be associated with fluctuating hormone levels and are predominantly found in premenopausal women due to higher estrogen levels 3
- The disease progresses with advancing premenopausal age and is most pronounced in women during their 40s, with regression typically occurring during the postmenopausal period 2
Classification Within Benign Breast Disease
- According to the American College of Radiology, benign breast disease is classified into three broad categories: nonproliferative lesions, proliferative lesions without atypia, and proliferative lesions with atypia 1
- Fibrocystic changes are specifically categorized as nonproliferative lesions, along with benign calcifications, fibroadenomas, lipomas, fat necrosis, and nonsclerosing adenosis 1
Clinical Presentation
- The clinical manifestations include breast and axillary pain or tenderness, development of fibrocystic plaques, nodularity, macrocysts, and fibrocystic lumps 2
- Patients present with breast pain, lumpiness, or cysts as the characteristic features 4
- The condition afflicts at least 50% of women of childbearing age, making it extremely common 5
Imaging and Diagnostic Features
- On ultrasound and mammography, fibrocystic changes appear as benign findings and are classified as BI-RADS Category 2 (benign finding) 1
- Simple cysts associated with fibrocystic changes are placed in BI-RADS Category 2, essentially indicating a report that is negative for malignancy 1
- Complex cysts and clustered microcysts may be classified as BI-RADS Category 3 (probably benign) requiring short-interval follow-up 1
Cancer Risk Implications
- Nonproliferative lesions like fibrocystic changes are independent risk factors for developing breast cancer, though the risk is lower compared to proliferative lesions 1
- Almost 30% of women with breast cancer have a history of benign breast disease 1
- The risk of breast cancer is increased twofold to fourfold in patients with fibrocystic disease, particularly when atypia is present on biopsy 2, 4
Important Clinical Distinction
- Fibrocystic changes must be distinguished from complex fibroadenoma, which includes sclerosing adenosis, papillary apocrine metaplasia, epithelial calcifications, and/or cysts greater than 3 mm 6
- Extensive cystic degeneration in a fibroadenoma (cystic fibroadenoma) is very rare and requires differentiation from other cystic lesions including cystic papilloma 6