Benign breast disease
Benign breast disease covers the nonmalignant conditions, fibrocystic change, fibroadenoma, phyllodes tumor, intraductal papilloma, and fat necrosis, that present as a breast mass, cyclical pain, or nipple discharge. Age-based imaging and, when indicated, core needle biopsy establish the diagnosis; most lesions are observed, while a fibroadenoma over 3 cm, a phyllodes tumor, or a papilloma is treated with surgical excision.
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What this article covers
- Overview
Definition: Benign breast disease is the umbrella term for nonmalignant conditions, chiefly fibrocystic change, fibroadenoma, phyllodes tumor, intraductal papilloma, fat necrosis, and simple cysts.
- Epidemiology
Fibroadenoma: The most common solid benign mass and the leading cause of a breast mass under age 30, peak ages 15 to 35, median diagnosis age 30 years; up to 20% of patients have more than one.
- Risk factors
Hormonal exposure: Estrogen and progesterone drive fibrocystic change and fibroadenoma growth; fibroadenomas enlarge in pregnancy and shrink after menopause, unlike carcinoma, which does not regress.
- Pathophysiology
Fibrocystic change: An exaggerated stromal response to cyclical hormones produces cysts, stromal fibrosis, and epithelial hyperplasia that fluctuate with the cycle.
- Clinical features
Fibrocystic change: Cyclical bilateral mastalgia and nodularity beginning in the luteal phase, about 2 weeks before menses, subsiding with menstruation; masses fluctuate rapidly with the cycle, unlike a fixed fibroadenoma.
- Differential diagnosis
Invasive breast carcinoma: a firm, immobile mass with ill-defined margins, unlike the discrete, mobile fibroadenoma; a new mass in a postmenopausal woman is treated as breast cancer until proven otherwise.
- Diagnosis
What establishes the diagnosis: a benign lesion is confirmed only when exam, the Breast Imaging Reporting and Data System (BI-RADS) category, and pathology are concordant; core needle or fine-needle…
- Management
First-line for a confirmed, imaging-concordant lesion, observe: a biopsy-proven fibroadenoma under 3 cm that is asymptomatic is followed with repeat exam or ultrasound at 6 to 12 months.
- Complications
Phyllodes recurrence: more likely with narrow margins than wide excision; rare malignant phyllodes tumors spread hematogenously to lung and bone rather than through axillary nodes.
- Prognosis
Nonproliferative lesions carry an RR of 1.27, close to baseline, unlike proliferative disease.
- Prevention
Age-based screening mammography, beginning between ages 40 and 50, is the foundation of early detection for a woman without a high-risk biopsy.
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- Paget disease of the breast
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- Inflammatory breast cancer
Inflammatory breast cancer is a clinically diagnosed, rapidly progressive form of locally advanced breast cancer causing diffuse erythema, edema, and peau d'orange from dermal lymphatic tumor emboli, often mistaken for mastitis. It is at least T4d (stage IIIB) at diagnosis and requires neoadjuvant chemotherapy followed by modified radical mastectomy and postmastectomy radiation; breast-conserving surgery is contraindicated.
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