What Are Breast Hematomas?

A breast hematoma is a collection of blood that forms under the skin's surface, very similar to having a large bruise in your breast. Although it is not cancerous, it could possibly be alarming to feel, as it may be painful or tender, or feel like a lump in the breast.

A breast hematoma can happen to anyone regardless of age or menopausal status. It may be caused by trauma or from medical procedures, like a breast biopsy or breast surgery. Breast hematomas are usually visible on a mammogram and can sometimes look suspicious on other imaging as well. Treatment usually consists simply of waiting for the hematoma to go away over time, but surgery may sometimes be needed.

This article will review the symptoms associated with a breast hematoma, as well as how it is diagnosed and treated.

Breast Hematoma Symptoms

You can usually see and feel a hematoma because it's often just below the skin, where blood has collected and clotted together. The pooled blood may cause inflammation and swelling. The skin above a hematoma can appear to be bruised and, in the case of surgery, broken.

When feeling a hematoma, it may feel like a firm lump beneath the skin. That can be frightening if you're familiar with the common symptoms of breast cancer.

Causes

A breast hematoma may be caused in several ways. Most of the time, you will recall an injury that caused the hematoma.

Possible causes of a hematoma include:

• Injury to the breast, such as a sports injury, car accident, or fall
• Weak blood vessel breaking in response to a bump or jolt
• Breast implant surgery (postoperative bleeding)
• Therapeutic (not cosmetic) breast surgery, such as a lumpectomy (removing cancerous or abnormal breast tissue) or mastectomy (removing the entire breast)
• Core needle breast biopsy (rare), with risk of a hematoma roughly doubling with a vacuum-assisted procedure

Those on aspirin or blood thinners, such as Coumadin (warfarin), Eliquis (apixaban), or Xarelto (rivaroxaban) are at particular risk for a hematoma regardless of meeting the criteria above.

If symptoms occur without an injury, the specific cause of the hematoma may need further investigation through surgery or anther procedure.

Diagnosis

Diagnosing a hematoma may require imaging of the breast and, in some cases, a biopsy.

A small hematoma probably won’t be seen on a mammogram. However, if the hematoma is large enough to be seen, it will usually appear as a well-defined oval mass. If it resolves on its own, it won’t appear on your next mammogram.

Spots on mammograms that are more suspicious for cancer appear with a spiky outline. Hematomas may have some suspicious-appearing features due to scarring or how the hematoma affected the breast tissue.

Hematomas often leave behind calcifications (calcium deposits) as well, but these are large in contrast to the microcalcifications on a mammogram that raise suspicion of possible cancer.

Hematomas are also found along with seromas, pockets of fluid in the breast that frequently occur after breast surgery. A breast ultrasound is often the best test for evaluating a possible seroma.

Hematoma vs. Tumors

In the case of a questionable breast mass, such as a hematoma that caused scar tissue and resembles a tumor, an ultrasound after an abnormal mammogram can detect if it is a hematoma. In some cases, a biopsy may be performed if the imaging continues to look suspicious. The pathology report can tell you whether the mass is benign (not cancerous) or malignant (cancerous).

Treatment

For small breast hematomas, no specific treatment may be needed. The body will absorb the blood from the bruise and it will eventually go away on its own. A heating pad or compress may help speed the process along.

Larger breast hematomas may need to be surgically removed. In some cases, it is possible for a breast hematoma to spontaneously recur.

Summary

Breast hematomas are a collection of blood in the breast. Although these can occur without an injury, most are due to an injury or surgical procedure. The hematoma may show up on breast imaging, and it may need a biopsy if it appears abnormal in any way. A hematoma is not cancer, and many times no specific treatment is needed.

A Word From Verywell

Breast hematomas can be uncomfortable and make people nervous, but they usually heal on their own in time. If the hematoma is large or you continue to have bleeding, it may need to be surgically removed. Let your healthcare provider know if a breast hematoma lingers and if you've had one that has resolved, as this will need to be taken into account when future mammograms are reviewed.