Most associated with moderate risk of breast carcinoma
1. Non-proliferative lesions:
These conditions are not associated with overgrowth of breast tissue.
They do not affect breast cancer risk, or if they do, it is to a very small extent. They include:
a. Fibrocystic disease (fibrosis and/or cysts)
b. Mild hyperplasia (an abnormal overgrowth of cells)
c. Adenosis (non-sclerosing, or non-hardening of tissuE.
d. Simple fibroadenoma
e. Phyllodes tumor (benign)
f. A single papilloma
g. Fat necrosis
i. Duct ectasia
j. Other benign tumors (lipoma, hamartoma, hemangioma, neurofibromA.
2. Proliferative lesions without atypia: These show excessive growth of cells in the ducts or lobules of the breast tissue. They seem to raise a woman's risk of breast cancer slightly (1½ to 2 times normal). They include:
a. Usual ductal hyperplasia (without atypiA.
b. Complex fibroadenoma
c. Sclerosing adenosis
d. Several papillomas or papillomatosis
e. Radial scar
Proliferative lesions with atypia: In these conditions, there is excessive growth of cells in the ducts or lobules of the breast tissue, and the cells no longer appear normal. They have a stronger effect on breast cancer risk, raising it 4 to 5 times higher than normal. They include:
i. Atypical ductal hyperplasia (ADH)
ii. Atypical lobular hyperplasia (ALH)
Women with a family history of breast cancer and either hyperplasia or atypical hyperplasia have an even higher risk of developing a breast cancer.