Sclerosing adenosis refers to a proliferative breast lesion in which various elements have become hardened, damaged, or otherwise distorted. Importantly, this type of breast lump is a benign lesion, but medics can sometimes confuse it with tubular carcinoma, particularly if some lobular neoplasia is evident.
This type of lesion may be completely asymptomatic, or can present as a palpable mass in a clinical exam.
Sclerosis means ‘hardening’
‘Adenosis’ means increased in number and ‘sclerosis’ means hardening.
Histologically, (a tissue examination after biopsy) sclerosing adenosis often presents as a proliferation of elongated, obliterated or distorted glands and tubules.
In addition, there is hardening of the surrounding collagen and stroma tissue. The condition is sometimes called fibrosing adenosis or adenofibrosis, and tends to arise from problems with the terminal duct lobular unit (TDLU).
Here is a picture of the Histopathology.
On a mammogram, sclerosing adenosis is rather variable in its presentation. It usually appears bilaterally, and often with diffuse and scattered microcalcifications. However, it can also present as an asymmetric density with microcalcifications, a solitary cluster of microcalcifications or as a non-calcified mass.
When these rarer, unusual presentations occur, it is best to have a biopsy to verify the findings. When it presents as a mass it is referred to as either ‘nodular adenosis’ or ‘adenosis tumor’, but it is not a tumor and is not cancerous.
Sclerosing adenosis and breast Cancer
The development of this condition has no direct link to breast cancer. It is not ‘pre-cancerous’. However, as is the case with many common benign breast abnormalities, malignant lesions can sometimes develop within them.
Sclerosing adenosis and risk of breast cancer
Over the long term, it is thought that sclerosing adenosis increases the risk of subsequent breast cancer development approximately two times.
However, to clarify, this does not mean that the sclerosing lesion causes the increase in breast cancer risk. What it does means, is that the same genetic predispositions which have brought about the sclerosing adenosis, will also give a woman an increased predisposition towards possible breast carcinoma development.
We have room to take a few questions here
What is nodular sclerosing adenosis?
This is the same as normal adenosis but the abnormalities have a rounded shape that looks like a nodule.
What does it feel like?
It feels hard, and so you worry it is a lump or nodule.
How to treat it?
It does not actually need treatment but often the pathology report adds more scary words. This in turn can worry some patients and sometimes they may just want the whole thing surgically removed. This treatment is excisional biopsy.
What causes the calcifications in sclerosing adenosis?
The same guesses apply here. Nobody can say exactly, but I think the fibrosis just traps some debris from dying cells and that stuff slowly turns hard and calcifies.
Should I get an ultrasound?
Usually yes, because if ultrasound can find a target to biopsy it is the easiest, quickest, most painless way to get a biopsy done.
Radial scar is a ‘duct’-related thing, and adenosis is more ‘lobule’-related. But they look VERY similar on mammogram.
- Kinko Z, Michal M. (2004) Anogenital mammary type sclerosing adenosis–two case reports and the review of literature. Ceska Gynekologie.2004; 69(4):292-7. https://www.ncbi.nlm.nih.gov/pubmed/15369249
- Kornguth P, Bentley R. (2001) Mammographic-Pathologic Correlation: Part 1. Benign Breast Lesions. Journal of Women’s Imaging:Volume 3 (1) February 2001 pp 29-37
- Krieger N, Hiatt RA. (1992) Risk of breast cancer after benign breast diseases: variation by histologic type, degree of atypia, age at biopsy, and length of follow-up. Am J Epidemiol 1992;135:619-631. https://www.ncbi.nlm.nih.gov/pubmed/1580238
- Tavassoli FA. (1999) Pathology of the Breast. Second edition. Stamford, CT: Appleton &Lange, 1999.