- Non-cancerous Breast Conditions
- What is normal breast tissue and what does it do?
- Finding benign breast conditions
- American Cancer Society recommendations for early breast cancer detection
- Diagnosing benign breast changes
- Imaging tests for breast disease
- Nipple discharge exam (nipple smear)
- Types of non-cancerous breast conditions
- Fibrosis and simple cysts
- Lobular carcinoma in situ
- Phyllodes tumors
- Intraductal papillomas
- Granular cell tumors
- Fat necrosis and oil cysts
- Duct ectasia
- Other benign breast conditions
- How benign breast conditions affect breast cancer risk
- For women at increased breast cancer risk
- Additional resources
In adenosis, the breast lobules are enlarged, and they contain more glands than usual. Adenosis is often found in biopsies of women with fibrocystic changes. There are many names for this condition, including aggregate adenosis, tumoral adenosis, or adenosis tumor. Even though some of these terms contain the term tumor, this condition is benign and is not a cancer.
Sclerosing adenosis is a special type of adenosis in which the enlarged lobules are distorted by scar-like fibrous tissue.
If many enlarged lobules are close to one another, they may be large enough to be felt. When this is the case, it may be hard for the doctor to tell these lumps from a breast cancer with only a breast exam. Calcifications (mineral deposits) may form in adenosis, in sclerosing adenosis, and in cancers. These can be confusing on mammograms.
Because adenosis can often be confused with cancer based on breast exams or mammograms, a biopsy is usually needed to tell them apart. Fine needle aspiration (FNA) biopsy of these lumps can usually show if they are benign. A core needle biopsy can usually identify the mass as adenosis, but sometimes a surgical biopsy is needed to be sure it is not cancer.
Some studies have found that women with sclerosing adenosis have a greater risk of developing breast cancer—about 1½ to 2 times the risk of women with no breast changes.
Last Medical Review: 08/24/2012
Last Revised: 08/24/2012