Breast oil cysts arebenign(noncancerous) breast lumps.
They often feel similar to the lumps common to breast cancer.
They may be diagnosed on ultrasound or other breast imaging.
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Oil cysts in the breast commonly occur due to injury to the chest or medical procedures.
They often feel soft and squishy.
They typically don’t require treatment.
Breast oil cysts do not become cancerous, and they do not increase the risk of developing breast cancer.
However, in rare cases, they may occur in association with underlying cancer.
Any mass that can be felt or is concerning on imaging tests should be evaluated by your healthcare team.
This article discusses the symptoms, causes, diagnosis, and treatment of breast oil cysts.
Symptoms
When breast oil cysts are small, they often go unnoticed.
As a cyst gets larger, it may be found during aself-breast exam.
Sometimes cysts are found when they are seen on a mammogram or other imaging tests.
Some breast cysts can grow larger over time.
If they occur after surgery or trauma, there may also be bruising associated with the cyst.
They are called oil cysts because they contain a liquid form of body fat.
How They Develop
During alumpectomyormastectomy, there can be damage to the fat cells of the breast.
As the fat cells break down (breast fat necrosis), their structure changes.
The damaged fat cells can form into hard scar tissue or an oily liquid.
When liquid fat collects in one area, a thin layer of calcium can form a wall around it.
Typically, oil cysts are usually partially or totally enclosed by calcium.
They can also occur after a breast biopsy or cancer removal (mastectomy).
In males, most breast oil cysts are associated with trauma.
Cysts are filled with fluid, gas, or semisolid substances.
This causes them to appear on ultrasound as dark, smooth-edged circular or oval areas.
The cysts have a clear outline that distinguishes them from surrounding tissues.
Aseroma(fluid-filled cyst) can appear identical to an oil cyst on ultrasound.
Breast MRI
At times, benign breast lumps can look very similar to cancer on imaging tests.
The radiologist will compare any concerning areas to the surrounding tissue to help determine if further testing is needed.
Generally,breast MRIis used for diagnosis and staging of breast cancer, rather than as a screening tool.
However, your provider may recommend it to get the very detailed internal pictures that MRI can produce.
Oil cysts will show up on a breast MRI but are best diagnosed using breast ultrasound.
The cell death and inflammation may look similar to an oil cyst on some imaging.
Treatment Options
Breast oil cysts are benignthey are not cancerous.
They do not causebreast canceror increase your risk of developing breast cancer.
Therefore, an oil cyst may be left alone.
This is often called “watchful waiting.
Many times, these will shrink or go away on their own without treatment.
Your team will work to distinguish an oil cyst from a possible cancer recurrence.
They most often develop after trauma or damage to the breast.
Cysts may be seen on a mammogram, breast ultrasound, or MRI.
Breast oil cysts can usually be left alone.
The fluid can be aspirated for removal and to confirm the diagnosis.
With aspiration, the oil cysts usually deflateboth resolving the cyst and the anxiety that can accompany having them.
Fat necrosis results when thick, fibrous scar tissue replaces the damaged fat cells.
Breast cysts can grow at varying rates, so your experience will be unique.
Some breast oil cysts never grow enough to be felt during a breast exam.
Oil cysts are typically harmless.
They sometimes go away on their ownbut this can take months to years.
If your cyst is bothering you, your provider may be able to drain it or surgically remove it.
There is no strong scientific evidence that this is an effective remedy.
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