A radial scar is a form of sclerosing duct hyperplasia. There is typically no solid, dense central tumor corresponding to the size of the spicules. But, often there are translucent, circular, or oval regions in the center of the radiating structure that gives the radial scar a characteristic ‘star-like’ appearance.
Radial scars may indicate a disturbance in the breast tissue and more specifically between the stromal (supportive) and functional elements (lobules, ducts, etc), that can lead to the formation of scar tissue, or possibly to cancer.
There is a newer version of this page with more up-to-date information on lots of conditions including Radial Scars.
Radial scar and risk of Breast Cancer Development
Studies conclude that a finding of a radial scar increases the risk factor for breast cancer. Women with a radial scar are at a higher risk for breast cancer development. This increase in risk ranges approximately from 8% to 30%.
Ultrasound does not show Radial Scar
A mammogram may detect a radial scar as a kind of star-shape feature with spiculated contours and no, or little, central mass. Radial scars are not detectable using ultrasound imaging. However, a biopsy will usually confirm a radial scar.
The image below is a mammogram of a radial scar.
Biopsy is Necessary for Diagnosis
The spiculated, star-like configuration of the radial scar can resemble tubular carcinoma. So, to establish a differential diagnosis, a biopsy is taken and a pathologist will examine the tissue sample under the microscope.
Typically one of two stains is applied to the tissue: either hematoxylin-eosin or immunohistochemical actin. A finding of healthy myoepithelial cells in the histological work up excludes the diagnosis of tubular carcinoma.
Differential diagnosis: Ruling out tubular Carcinoma by Biopsy
The images below are histology slides of breast tissue and show benign ducts within a sclerotic stroma, thus ruling out the possibility of tubular carcinoma.
The breast tissue in both of these images has much thicker collagen (fibrous tissue) than average, and would, in fact, feel much harder to the touch than normal.
Hematoxylin-eosin, and staining actin
Hematoxylin-Eosin is a type of stain, applied to the tissue which makes things look a certain way under the microscope.
The second image uses a stain, ‘staining-actin‘, often used to find smooth muscle tissue (actin). The actin stain shows the smooth muscle as the darker-brown color where muscle cells are lining the outside of ducts (tubules).
In both images above, the absence of any kind of abnormality affecting the epithelial lining of the tubules rules out tubular carcinoma and confirms the diagnosis of radial scar.
Excisional biopsy reduces ‘false negatives’
There is some danger of ‘false negative’ findings if there are only very small samples for biopsy. Small samples are often obtained by fine needle aspiration or a needle core biopsy.
It is not uncommon for a radial scar or complex sclerosing lesion to contain small amounts of malignant breast cancer cells. An excisional biopsy is usually necessary.
Some Common and quick Q and A’s
What is a radial scar of the breast?
A radial scar of the breast, and also known as complex sclerosing lesion of the breast, is a benign breast lesion that can radiologically mimic malignancy (cancer).
What is radial scar associated with?
Radial scar carries an increase in the risk for breast cancer in both breasts, not only within the breast it occurred.
How do Medics Diagnose Radial Scar?
A surgeon will take a biopsy of a sample of the tissue. Next, a pathologist will examine the tissue for histology and morphology under the microscope.
What is histomorphology?
Radical scars are spiculated masses. So typically, under microscope, radial scars have a sclerotic appearing (scar like) center with peripheral entrapped normal breast ducts and lobules.
How are radial scars managed?
An excision of a radial scar is often necessary to exclude malignancy. However, doctors may also consider follow -up observation following a core biopsy.
- Brenner RJ, Jackman RJ, Parker SH, Evans WP. Philpotts L, Deutch BM. (2002) Percutaneous Core Needle Biopsy of Radial Scars of the Breast: When Is Excision Necessary?. Am. J. Roentgenol. 179: 1179-1184 https://www.ncbi.nlm.nih.gov/pubmed/12388495
- Douglas-Jones A, Denson J, Cox A, Harries I, Stevens G. (2007) Radial scar lesions of the breast diagnosed by needle core biopsy: analysis of cases containing occult malignancy. J Clin Pathol 2007;60:295-298 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1860566/
- Jacobs TW. (et al). (1999) Abramson Cancer Center of the University of Pennsylvania.The New England Journal of Medicine Vol. 340 No. 6 p.430 February 11, 1999
- Mokbel K, Price RK, Carpenter R, Jacobs TW, Connolly JL, Schnitt SJ. (1999). Radial Scars and Breast Cancer. NEJM 341: 210-210 https://www.ncbi.nlm.nih.gov/pubmed/10409044
- Tabar Laszlo. (2001) Teaching Course in diagnostic breast imaging: Multimodality approach to the detection and diagnosis of occult breast cancer. Mammography Education, Inc. 2001.