Benign Breast Conditions

What are benign breast conditions?

Benign breast conditions (also called benign breast diseases) are noncancerous disorders of the breast. They can occur in both women and men.

There are many types of benign breast conditions. Your health care provider may use the term fibrocystic change to describe a range of benign breast conditions.

This section discusses benign breast conditions in women.

Learn about benign breast conditions in men.

When is treatment or follow-up needed for benign breast conditions?

Some benign breast conditions cause discomfort or pain and need treatment. Some may need to be removed. Others don’t need treatment.

Many benign breast conditions mimic signs and symptoms of breast cancer. These conditions need follow-up tests and sometimes a breast biopsy for diagnosis.

IIf you need a biopsy, it’s normal to worry while you’re waiting for the results. It may be helpful to know most breast biopsies in the U.S. don’t find cancer [12]. Still, a biopsy is needed to know whether or not something is cancer.

Are benign breast conditions linked to an increased risk of breast cancer?

Benign breast conditions are not breast cancer. However, proliferative breast conditions (those that have quickly growing cells) and those with abnormal-looking cells are linked to an increased risk of breast cancer.

For example, women who have atypical hyperplasia have an increased risk of breast cancer [13-16].

Learn more about hyperplasia and breast cancer risk.

What increases the risk of benign breast conditions?

A few factors are linked to an increased risk of benign breast conditions, including [17-18,225]:

Menopausal hormone therapy (postmenopausal hormone use)
A family history of breast cancer or benign breast conditions

Learn about menopausal hormone therapy and breast cancer risk.

Learn about a family history of breast cancer and breast cancer risk.

Lifestyle factors during childhood and the teen years linked to the risk of benign breast conditions

Lifestyle factors linked to an increased risk of benign breast conditions

Some lifestyle factors during childhood and the teen years may be linked to an increased risk of benign breast conditions in adulthood. For example, women who drank alcohol during their teen years may have an increased risk of benign breast conditions [19-22].

Learn about lifestyle factors in childhood and the teen years that may be linked to breast cancer.

Lifestyle factors linked to a decreased risk of benign breast conditions

Some lifestyle factors during childhood and the teen years may be linked to a decreased risk of benign breast conditions in adulthood. For example, women who ate nuts (including peanut butter), beans and foods that contain carotenoids (such as melons, carrots and sweet potatoes) during their teen years may have a decreased risk of benign breast conditions [22-25].

Also, girls who are heavy at age 10 may have a lower risk of benign breast conditions in young adulthood than girls who are lean at age 10 [24,26]. Similarly, women who were heavy as children and teens may have a lower risk of breast cancer than women who were lean in their youth [27-33].

However, being heavy during childhood and the teen years is not advised as it’s linked to an increased risk of heart disease and many other health conditions in adulthood [34].

These topics are under study.

Learn about lifestyle factors in childhood and the teen years that may be linked to breast cancer.

Types of benign breast conditions

Benign breast conditions differ from each other in how the cells and their growth patterns look under a microscope. For example, hyperplasia looks different from a fibroadenoma.

If you’re told you have a benign breast condition (or a fibrocystic change), ask your health care provider which type you have, if it needs treatment and if it increases your risk of breast cancer.

There are many types of benign breast conditions. Some of the more common benign breast conditions are described below. This is not an exhaustive list.

Click on the topics below to learn more.

Hyperplasia describes a proliferation (overgrowth) of cells. It most often occurs on the inside of the lobules or milk ducts in the breast.

There are 2 types of hyperplasia: usual hyperplasia (more common) and atypical hyperplasia (less common). With usual hyperplasia, the proliferating (dividing) cells look normal under a microscope. With atypical hyperplasia, the proliferating cells look abnormal.

Hyperplasia and breast cancer risk

Women with atypical hyperplasia have about 3 to 5 times the breast cancer risk of women without a proliferative breast condition [13-16].
Women who have usual hyperplasia about twice the breast cancer risk of women without a proliferative breast condition [13-14].

Learn more about hyperplasia and breast cancer risk.

For a summary of research studies on hyperplasia and breast cancer, visit the Breast Cancer Research Studies section.

Breast cancer screening for women with atypical hyperplasia

For women with atypical hyperplasia who also have a 20% or greater lifetime risk of invasive breast cancer, there are special breast cancer screening recommendations. (Estimate your lifetime risk or learn more about risk.)

The National Comprehensive Cancer Network (NCCN) recommends women with atypical hyperplasia who also have a 20% or greater lifetime risk of invasive breast cancer [226]:

Have a clinical breast exam every 6-12 months
Have a mammogram with digital breast tomosynthesis every year, starting at age 30
Talk with a health care provider about screening with breast MRI every year, starting at age 25

This medical care helps make sure if breast cancer develops, it’s caught early when the chances of survival are highest.

Learn more about breast cancer screening for women at higher risk.

Risk reduction for women with atypical hyperplasia

The NCCN strongly recommends women with atypical hyperplasia (but not usual hyperplasia) take a risk-reducing drug (such as tamoxifen) to lower their risk of breast cancer [227].

Taking a risk-reducing drug can lower the risk of breast cancer in women with atypical hyperplasia by about 86% [227].

Learn more about breast cancer screening for women at higher risk.

Learn more about risk-reducing drugs.

For a summary of research studies on the use of risk-reducing drugs to lower the risk of breast cancer visit the Breast Cancer Research Studies section.

Cysts are fluid-filled sacs that are almost always benign (not cancer).

Cysts are most common in premenopausal women ages 35-50 [228]. After menopause, cysts occur less often [228].

Cysts and breast cancer risk

Most cysts are not linked to an increased risk of breast cancer [228].

Diagnosis of cysts

Most cysts are too small to feel. Some, however, are large and may feel like lumps in the breast and may cause breast pain [228].

Cysts are diagnosed with a breast ultrasound and/or a fine needle aspiration (fine needle biopsy) [228].

Treatment for cysts

Often, cysts don’t need treatment.

If they’re painful or can be felt, they can be aspirated (drained).

Risk factors for cysts

We don’t know what causes cysts to develop. They do not appear to be related to diet or other lifestyle factors.

Learn more about the early detection and diagnosis of cysts.

Fibroadenomas are solid benign (not cancer) tumors. They’re the most common benign tumor in the breast [229].

They occur most often in women ages 15-35 [229].

Often, a fibroadenoma doesn’t need treatment. However, if it’s large or causes discomfort, it may be removed [229]. It may also be removed if it’s worrying you [229].

Fibroadenomas and breast cancer risk

Most fibroadenomas are not linked to an increased risk of breast cancer [229].

Learn more about the early detection and diagnosis of fibroadenomas.

Intraductal papillomas are small growths that occur in the milk ducts of the breasts.

They are usually close to the nipple and can cause nipple discharge and pain. You may feel a lump.

They occur most often in women ages 35-55 [40].

Intraductal papillomas are removed with surgery, but don’t need any other treatment [41,229].

Intraductal papillomas and breast cancer risk

Women who have one intraductal papilloma don’t have an increased risk of breast cancer unless the intraductal papilloma has abnormal cells or there’s ductal carcinoma in situ (DCIS) in the nearby tissue [41,229].

Women who have 5 or more intraductal papillomas at the time of diagnosis may have an increased risk of breast cancer [229].

Sclerosing adenosis is made up of small breast lumps in a lobule of the breast. It may be painful, and you may feel a lump.

Sclerosing adenosis may be seen on a mammogram. Because it has a distorted shape, it may be mistaken for breast cancer. A breast biopsy may be needed to rule out breast cancer.

Sclerosing adenosis doesn’t need treatment [229].

Sclerosing adenosis may be found with atypical hyperplasia, lobular carcinoma in situ (LCIS) or ductal carcinoma in situ (DCIS) [40].

Sclerosing adenosis and breast cancer risk

Some studies have found sclerosing adenosis is linked to a slightly increased risk of breast cancer, while others have found no link between the two [43-44].

Radial scars (also called complex sclerosing lesions) have a core of connective tissue fibers. Milk ducts and lobules grow out from this core.

Although radial scars can look like breast cancer on a mammogram, they’re not cancer.

Radial scars are removed with surgery, but don’t need any other treatment [229].

Most often, radial scars are a secondary finding when a breast biopsy is done for other reasons [229].

Radial scars and breast cancer risk

Some studies have found radial scars are linked to an increased risk of breast cancer, while others have found no link between the two [45-48].

Radial scars are typically found alongside other breast conditions, which may explain these mixed findings [45].

Phyllodes tumors

Phyllodes tumors are fast-growing breast lumps that begin in the connective tissue of the breast [49]. They are usually painless [230].

The word “phyllodes” means leaf-like. This describes how phyllodes tumor cells look under a microscope.

Some phyllodes tumors develop slowly over time and some are fast-growing. Phyllodes tumors can be benign (not cancer), malignant (cancer) or borderline (of uncertain behavior).

With most phyllodes tumors, you can feel a breast lump. Sometimes, they appear as an abnormal finding on a mammogram.

They’re most common in women in their 40s [49,230].

Diagnosis and treatment of phyllodes tumors

Most phyllodes tumors are benign, but about 25% are cancerous [49,230].

A phyllodes tumor may be suspected on core needle biopsy findings. However, in most cases, the diagnosis is not certain until after surgery to remove the tumor [230]. A pathologist studies the tissue under a microscope to make the diagnosis.

For benign phyllodes tumors, surgery to remove the tumor is the only treatment needed [49,230]. Regular screening mammograms and other imaging tests may be needed as benign phyllodes tumors can recur (come back) [49,230].

If a benign phyllodes tumor recurs, another breast biopsy or surgery will be needed to confirm the diagnosis.

Malignant phyllodes tumors are rare invasive breast cancers. They account for fewer than 1% of all invasive breast cancers [230].

Learn about malignant phyllodes tumors.

Benign phyllodes tumors and breast cancer risk

Benign phyllodes tumors are not linked to an increased risk of breast cancer [49].

Fat necrosis is a breast lump usually caused by injury, surgery to the breast (including breast reconstruction) or radiation therapy to the breast [229,231].

Fat necrosis is made of damaged or dead fatty tissue cells in the breast and can change into scar tissue over time.

The skin around the lump may look red, bruised or thicker than the other skin of the breast [51]. The lump is usually painless [51].

Fat necrosis is more common in women with very large breasts than in other women [232].

Fat necrosis may mimic signs of breast cancer on a mammogram or clinical breast exam. A needle biopsy may be needed to confirm the diagnosis.

In most cases, fat necrosis doesn’t need to be surgically removed or treated [51,229]. Sometimes, it will go away on its own [51,229].

Fat necrosis and breast cancer risk

Fat necrosis is not linked to an increased risk of breast cancer [51,229].

Learn about breast reconstruction.

Learn about radiation therapy for breast cancer treatment.

Mastitis is inflammation (swelling) in the breast that may be painful. The breast may look red and feel warm. It can also cause flu-like symptoms or a fever. It’s usually caused by an infection.

Mastitis usually occurs when a milk duct becomes clogged in a woman who is breastfeeding [52].