Fibrocystic Change

Overview

Definition

• A non-specific term without a universally agreed upon definition
• Refers to benign changes in the breasts, particularly fibrosis and cysts
• Not associated with an increased risk of breast cancer

Classification of benign breast lesions

• Non-proliferative lesions 
  • Classic fibrocystic changes
  • Examples:
    • Fibrosis
    • Cysts
    • Adenosis (↑ number of acini per lobule)
• Proliferative lesions without atypia 
  • Generally not included in the term fibrocystic changes
  • Associated with a slight ↑ risk for cancer
  • Examples: 
    • Sclerosing adenosis
    • Epithelial hyperplasia
• Atypical hyperplasias
  • Not considered fibrocystic changes
  • Associated with an ↑↑ risk for cancer 
  • Often incidental findings on mammogram
  • Histologically similar to carcinoma in situ
  • Examples: 
    • Atypical ductal hyperplasia
    • Atypical lobular hyperplasia

Epidemiology

• Most frequent benign breast lesion
• Affects up to 50–60% of women
• Most common in women reproductive-age women, 30–50 years of age 
• Changes decrease (or resolve) with menopause.

Etiology

• Tied to estrogen and progesterone levels
• Risk factors:
  • Nulliparity
  • First live birth at age > 30 years old
  • Early menarche

Pathophysiology

Anatomy

• Breast tissue consists of: 
  • Epithelial components → glands and ducts
  • Stroma → adipose and fibrous connective tissue
• Lobules are functional units (milk-producing sacs), separated by Cooper ligaments
  • Each contains multiple acini (tubuloalveolar glands) and adipose tissue.
  • Acini empty into the lactiferous ducts.

Pathophysiology

• The pathogenesis is incompletely understood, but appears to be associated with hormone levels.
  • Estrogen stimulates ductal elements (including adenosis).
  • Progesterone stimulates stromal elements.
• Classic fibrocystic changes:
  • Cystic lesions: 
    • Derived from the terminal duct lobular unit
    • Form by dilation and obstruction of the efferent duct
    • Often associated with aprocine metaplasia
    • Grow and shrink cyclically as estrogen levels fluctuate → cyclic mastalgia
    • Blue-dome cysts: fluid-filled blue-brown unopened breast cysts
  • Fibrosis:
    • Ruptured cysts → chronic stromal inflammation → ↑ stromal fibrosis
    • Results in palpable firmness on exam
• Comparison with proliferative lesions without atypia:
  • Sclerosing adenosis
    • ↑ acini and intralobular fibrosis → enlarged and distorted lobules
    • Associated stromal fibrosis and interspersed glandular cells
  • Epithelial hyperplasia:↑ in number of epithelial cell layers in the ductal space or lobule

Clinical Presentation

Fibrocystic changes typically present in reproductive-aged women as either “lumpy breasts,” a discrete breast mass, or mammographic abnormalities found on routine screening. 

• Ill-defined, diffuse ↑ in breast consistency (firmness)
• Palpable breast lumps
  • Single mass or multifocal (more common)
  • Discrete, well-circumscribed, mobile, and compressible
  • May be tender or nontender
  • Size and number of lesions can fluctuate throughout the menstrual cycle
• Cyclic breast pain
  • Generally mid-cycle
  • Fullness or heaviness
• Findings are often similar in both breasts.

Diagnosis and Management

Diagnosis

The most important thing is to differentiate benign fibrocystic changes from malignant conditions. 

• Mammography:
  • Recommended for all women ≥ 30 years old with a breast mass
  • Reveals round or oval-shaped masses with defined boundaries 
  • May contain densities or dispersed calcifications
• Breast ultrasound:
  • Recommended for all women with a breast mass (including those < 30 years old)
  • Findings: 
    • Anechoic, well circumscribed, compressible lesions
    • Posterior wall enhancement
    • Thickened parenchyma
    • Increased echongenicity
  • Findings suspicious for cancer (these would be lacking in fibrocystic changes):
    • Thickened walls
    • Septa
    • Vascular flow
    • Solid or other echogenic components
    • Absence of posterior wall enhancement
• Core needle biopsy (CNB): 
  • Histologic evaluation of suspicious imaging findings
  • Possible benign findings include:
    • Cystic structures
    • Fibrosis of stromal tissue
    • Epithelial hyperplasia
    • Apocrine metaplasia

Management

• Observation:
  • For patients without significant discomfort 
  • Provide reassurance.
  • Routine breast screening based on age
• Treat pain:
  • Supportive bra
  • Warm compresses
  • Avoid caffeine (limited evidence)
  • Non-steroidal anti-inflammatory drugs (NSAIDs) or acetaminophen
• Hormonal issues:
  • ↓ or discontinue postmenopausal hormone replacement therapy
  • Oral contraceptive pills (OCPs)
    • Can help with cyclic pain
    • Produces negative feedback for endogenous estrogen production
    • May need to ↓ estrogen component in some patients
• For severe symptoms:
  • Danazol (androgen)
  • Tamoxifen (estrogen receptor antagonist)
  • Bromocriptine (dopamine agonist)
  • Fine needle aspiration of cysts

Differential Diagnosis

• Fibroadenoma: a benign, solid breast mass composed of fibrous and glandular tissue. This presents as a small, well-defined, mobile mass with a rubbery or firm consistency. The exact etiology is unknown. Diagnosis is confirmed with a CNB. Management is either excision or observation.
• Phyllodes tumor: a fibroepithelial tumor similar to fibroadenomas, usually characterized by rapid growth. They may behave like benign fibroadenomas, or they may become malignant and metastasize. Phyllodes tumors are associated with Li-Fraumeni syndrome. Diagnosis is by CNB and management involves complete resection, with adjuvant radiation in malignant cases.
• Galactocele: a cystic collection of fluid usually caused by an obstructed milk duct. They present as a palpable, firm mass in the subareolar region, and may show a classic fat-fluid level on imaging. Diagnosis is based on history and aspiration, yielding milky fluid. These lesions do not require excision, but this may be considered for significant discomfort.
• Mastitis or breast abscess: inflammation of the breast tissue, most commonly due to infection with skin or oral flora introduced during breastfeeding. A purulent abscess may form. Occasionally non-lactational mastitis and abscess are also possible. Cases usually present with a fever, breast pain, erythema, edema, and a possible tender, fluctuant abscess. The diagnosis is clinical. Management involves antibiotics, continued expression of breast milk if lactating, and incision and drainage of an abscess.
• Fat necrosis of the breast: usually due to breast injury resulting in liquefactive necrosis of the adipose tissue. As the damaged breast tissue is repaired, there is progressive fibroblastic proliferation resulting in scar tissue. Calcifications may appear and can be difficult to distinguish from a malignant mass. Management involves supportive measures for pain control, but this condition is usually self-limited and does require further treatment.
• Malignant breast lesions: the most common types of breast cancer are invasive ductal carcinoma and lobular carcinoma. Most patients are asymptomatic, and a breast mass may be picked up on standard cancer screening (mammography). Diagnosis is made with a core needle biopsy. Management may involve surgery, chemotherapy, radiation, and hormonal treatment.