Breast Calcifications on Your Mammogram: What to Know

Breast calcifications are calcium deposits that appear as white dots on a mammogram. They can vary in size, as well as pattern and arrangement, and the significance of these factors can vary considerably.

Calcifications often are associated with breast cancer but there are other potential causes, such as benign (noncancerous) fibroadenomas.Calcifications are, in fact, quite common, affecting half of all women over the age of 50. The vast majority of these will be non-cancerous.

This article explains the characteristics of calcifications viewed on mammogram and what they may mean in terms of needing additional tests, such as a biopsy, to determine a diagnosis.

Types of Breast Calcifications

There are two types of breast calcifications, and they often mean very different things. Instead of using the following terms, your healthcare provider may simply call them large (macrocalcifications) or small (microcalcifications).

Macrocalcifications

Macrocalcifications are large bits of calcium deposits found on a mammogram. They may be due to other changes in a woman's breast, like hardening of her breast arteries. Macrocalcifications may also represent areas of inflammation from an old injury or breast trauma.

There is usually no need to worry about breast cancer with these larger breast calcifications. They are not usually linked to breast cancer and are more common in women 50 and older.

Microcalcifications

Microcalcifications are tiny bits of calcium deposits that may be an early sign of breast cancer, although they aren't always.

Pattern and Shape of Breast Calcifications 

The pattern and shape of microcalcifications are often different depending on whether the finding is benign or malignant (cancerous). For example, certain calcification patterns called teacup-like are typically benign. This is also likely true when they are described as:

• Eggshell-like
• Railroad tracks
• Rim-like
• Popcorn-like
• Coarse
• In a loose cluster pattern

A high volume of calcifications that don't follow milk ducts in the breast is also a sign they may not be cancerous.

Calcifications that are irregular in size or shape, such as spiculated (spiky) calcifications, may be suspicious. Calcifications arranged in a tight cluster also raise concerns about cancer.

Benign (Noncancerous) Causes of Calcifications

Breast calcifications arise from different causes, both those that are benign and those that suggest malignancy.

For example, scar tissue related to old breast injuries (dystrophic changes) can occur. Or it may be left over from prior breast cancer surgery (fat necrosis), injuries or trauma to the breast, or simply due to the natural wear and tear of the breasts.

Other benign causes of breast calcifications include:

• Mastitis or inflammation caused by a breast infection
• Calcium collected inside a dilated milk duct
• Calcium mixed with fluid in a benign breast cyst
• Radiation treatment for breast cancer
• Calcification in the arteries within your breast
• Calcifications in a fibroadenoma (benign growth)

Fibrocystic breast disease, which is related to normal hormonal changes in the body, also can lead to breast calcifications. Most changes are benign and very common. However, certain changes are associated with a clearly increased risk of breast cancer. They are called:

• Flat epithelial atypia (abnormal changes in cells that line the ducts)
• Atypical ductal hyperplasia (a precancerous condition also affecting ducts)
• Atypical lobular hyperplasia (precancerous changes affecting lobes of the breast)

These changes may be associated with ductal carcinoma in sutu (DCIS), an early and highly treatable "stage 0" breast cancer diagnosis. DCIS is often suspected when microcalcifications appear on a mammogram.

How Breast Calcifications Are Diagnosed

Breast microcalcifications most often appear on routine screening mammograms. If there is a concern about breast changes, a diagnostic mammogram may be ordered to get a more clear and precise view.

If the findings from the imaging suggest breast cancer, a biopsy is recommended. A biopsy means that a small area of the suspicious breast tissue is removed and examined under a microscope for cancer cells.

The most common procedure after calcifications are found is a stereotactic breast core biopsy. In this procedure, the healthcare provider uses imaging to guide the process and make sure tissue from the suspicious area is sampled.

Treatment of Breast Calcifications

Benign breast calcifications do not need treatment. If your healthcare provider determines that they are not cancerous, you do not need to have your breast calcifications removed.

However, calcifications revealed on a mammogram can sometimes alert healthcare providers to breast cancers that would otherwise go undetected. Experts are learning that breast calcifications also may provide information about the prognosis of breast cancer.

According to a 2018 study, breast cancers that have microcalcifications are more likely to:

• Be HER2-positive (a specific genetic type of cellular change in breast cancer)
• Be a higher tumor grade
• Have already spread to lymph nodes
• Present a greater risk of recurrence

This information may be helpful for women with early-stage breast cancers who are weighing the benefits of treatments such as chemotherapy after surgery.

Summary

Breast calcifications are a very common finding during routine mammogram screenings. Since more people now have access to mammograms, more of them are being found—and that's leading to more diagnoses of early-stage breast cancers like DCIS.

However, most calcifications are benign and don't lead to cancer. If a radiologist is concerned about certain shapes and patterns that may point to breast cancer, they are likely to repeat the imaging with a diagnostic mammogram. The additional clarity may lead to a biopsy to definitively determine if cancer cells are present.

Calcifications don't require treatment unless breast cancer is detected. Your healthcare provider will explain any next steps in your care.

A Word From Verywell

Healthcare providers do not always mention the word calcifications when talking to women about their mammograms. They may instead mention a "small abnormality." Ideally, you should ask for your report so that you can review it. Ask specifically what was found if you have an abnormal result, and be sure to ask about the description and pattern of any calcifications.