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Causes of Breast Lumps That Aren’t Breast Cancer

April 29, 2021

For women, noticing a mass in the breast can be frightening, with your mind naturally leaping to breast cancer as the cause. But many breast masses aren’t related to breast cancer.

“There are more than a dozen causes of breast masses that aren’t related to breast cancer,” says Dean Currie, MD, general surgeon with West Tennessee Medical Group Jackson Surgical Associates. “While any mass should be examined by a medical provider, it’s important to remember that there are many different types of benign breast masses. It’s very common for a woman to notice a breast mass that’s not cancerous.” 

Dean Currie, MD

But if a breast mass isn’t related to cancer, what causes it? Let’s take a deeper dive into the topic.

But First, Let’s Touch on Breast Cancer
Obviously, breast mass can be a sign of breast cancer. If you notice a breast mass during a self-exam or at another time, it’s important to let your OB/GYN or other medical provider know about it.

He or she will likely recommend you come in for a physical exam, and then depending on what is seen, you may also need to undergo a diagnostic mammogram, and often an ultrasound. 

How can you tell if the breast mass you spot is cancerous? Well, you really can’t. While noncancerous breast masses typically have smooth edges and can be moved manually with the fingers, that isn’t always the case.

The only way to tell for certain is to have a provider take a look and order testing as necessary.

Other Types of Breast masses
Now that we’ve talked a little about breast cancer, what about noncancerous breast masses? Like we mentioned earlier, there are multiple types of benign breast changes, including masses.

In fact, breast tissue changes throughout life for a variety of reasons, including hormonal fluctuations due to menopause or pregnancy, infections and trauma.

Here are a few common benign causes of breast masses:

  • Adenosis. This medical condition occurs when the lobules, which are milk-producing glands, become enlarged, with more glands than normal. When the glands cluster together, they can be felt as a breast mass.
  • Cysts. These noncancerous growths are a common cause of breast masses. Breast cysts are simply benign changes in the breast tissue that many women experience at some time during life. They appear as fluid-filled sacs that may be tender to the touch.
  • Duct ectasia. This condition is related to the milk ducts, hence the name “duct ectasia.” It occurs when a milk duct widens and its walls thicken, which can cause the duct to become blocked, sometimes causing a mass.
  • Fat necrosis. This type of breast mass occurs when an area of fatty breast tissue is damaged, usually as a result of trauma to the breast. As the body repairs the damage, the tissue is replaced by firm scar tissue, which can be felt as a breast mass. In some cases, damaged fat cells in the breast may die off, releasing their contents into the body. This can cause breast oil cysts, which can also give the appearance of a breast mass.
  • Fibroadenomas. These are a type of noncancerous breast tumor that’s made up of a combination of glandular tissue and stromal (or connective) tissue. They often feel like a marble under the skin of the breast.
  • Fibrosis. This is the name for a large amount of fibrous tissue, which is the tissue that ligaments and scar tissue are made of, appearing firm to the touch.
  • Lobular carcinoma in situ. This one sounds like it’s cancerous, but it’s actually not. Instead, it could be more aptly called an imposter. It’s a type of breast change that causes cells that look like cancer cells in the lining of the milk-producing glands. While these breast changes are not cancerous, having them can increase your chance of developing breast cancer later on, so it’s important to seek medical attention.
  • Mastitis. Most women who have breastfed are familiar with mastitis, which is a condition that occurs most commonly in breastfeeding mothers. This condition occurs when a milk duct is clogged, often leading to an infection and sometimes a breast abscess that will need to be drained.

If you notice a breast mass, get in touch with your medical provider who can advise you on next steps. You’ll likely be asked to come in for a visit and potentially to have other testing done to determine the type of breast mass and whether it requires treatment.

West Tennessee Medical Group Jackson Surgical Associates has been providing expert, compassionate surgical care to those in west Tennessee for more than 50 years. Call (731) 664-7395 to learn more or to schedule an appointment for a surgical consultation.