BENIGN BREAST DISORDERS:

Fibroadenomas

Etiology: Benign* solid tumors resulting from excess growth of connective tissue; both fibrous and glandular components; 20% cases multiple or bilateral fibroadenomas, *up to 0.3% chance of malignant transformation.

Epidemiology: Most common in women between ages 15-35; Sensitive to hormonal changes; Enlarge in pregnancy and involute after menopause

Clinical presentation: Mobile, palpable mass (breast “mouse”)

Diagnosis: By imaging in practice, but definitive diagnosis only with core biopsy or excision

Imaging:

–     US: Ovoid or macrolobulated shape; circumscribed margins; wider than tall/parallel configuration; uniformly hypoechoic; thin echogenic pseudocapsule

–     Mammogram: Circumscribed to multilobulated mass; "popcorn" calcification representing fibroadenoma involution (post-menopause)

Management: Short term follow-up ultrasound for presumed fibroadenomas with classic, benign imaging findings. In case of interval increase in size, must excise to rule out malignant transformation or Phyllodes tumor. Surgical excision or cryoablation if symptomatic.

(Ikeda 2010, Georgian-Smith 2014, Sabel 2015)