“Fibrocystic disease” is the wastebasket term for benign breast disease characterized by fibrosis, cysts, inflammation, and a host of other benign changes.
Benign lesion that is the cause of most breast lumps found in younger women of reproductive years (age 30-menopause)
Fibrocystic changes of the breast are NONPROLIFERATIVE and have NO increased risk of cancer in and of themselves.
Atypical hyperplasia (ductal or lobular) can mean there is an adjacent in situ or invasive cancer
Old lady notices an ill defined lump in her breast.
Childbearing-aged lady complains her breast is “lumpy bumpy” all over.
Lesion “disappears” after FNA (because cyst fluid was drained to be sent for cytologic diagnosis)
Common Findings in Fibrocystic Changes
Irregular, cystically dilated ducts/lobules
Cysts are lined by uniform benign cuboidal to columnar epithelial cells
FNA of fluid from cyst= benign appearing cells
Intervening stromal fibrosis
One or more mammographic densities (dense breast tissue & cysts) +/- calcifications
Sclerosing Adenosis: Calcifications, focal asymmetry, architectural distortion
Columnar cell change ± flat epithelial atypia: Calcifications
Papilloma: Mass, calcifications
Radial sclerosing lesion: Architectural distortion, calcifications
Lobular neoplasia (ALH, LCIS): Typically incidental findings in biopsies for other lesions
Nonclassical LCIS can be associated with necrosis and calcifications
Atypical ductal hyperplasia: Calcifications
Histologic Patterns of FCC
Cyst formation/Duct ectasia
Pseudoangiomatous Stromal Hyperplasia (PASH)
Sclerosing adenosis (adenosis= increased number of acini per lobule)
Apocrine metaplasia (large, tall, columnar epithelial cells with abundant pink cytoplasm lining the cysts, may be vacuolated)
Columnar Cell Changes
Flat epithelial atypia