Fibrocystic Changes

FIBROCYSTIC CHANGES

Fibrocystic changes (formerly called fibrocystic disease) are a group of very com-mon, benign changes that can be classified as proliferative (having an increase in the glandular elements or epithelial cells) or nonproliferative. Because they carry varying degrees of risk for breast cancer, it is important to identify each type his-tologically.

Fibrocystic changes primarily affect women in their reproductive years. The changes most often involve the upper outer quadrant and may produce a palpable mass or nodularity.

•         Fibrosis may mimic a tumor on clinical exam and U/S.

•         Cysts can usually be diagnosed by U/S.

•         Apocrine metaplasia is often seen in cyst walls.

•         Microcalcifications occur in benign and malignant processes.

•         Ductal hyperplasia is classified as usual or atypical on the basis of cytology and microlumen architecture; atypical ductal hyperplasia is differentiated from DCIS on the basis of microscopic extent.

•         Atypical lobular hyperplasia is differentiated from LCIS histologically on the basis of the percentage of acini involved.

•         Sclerosing adenosis is distinguished from carcinoma histologically by the preservation of the myoepithelial layer