Patient information from BMJ

Breast lumps, non-cancer (benign)

Last published:May 19, 2022

If you find a lump in your breast you’ll probably worry that it could be cancer. And, of course, you should see your doctor to have it checked.

But most breast lumps are what’s called 'benign'. This means that they are not cancer and are usually not dangerous. In this leaflet, we explain the most common causes of benign breast lumps.

What are non-cancerous (benign) breast lumps?

A benign breast lump is simply a lump (your doctor may call it a mass) in your breast that isn’t caused by cancer.

About 90 in every 100 women who see their doctor because of a lump in their breast don’t have cancer.

Doctors have several ways of finding the cause of benign breast lumps. The first thing they will do is examine you, by looking at your breast and gently feeling the lump. This can help to tell what kind of lump it is and what has caused it.

There are also tests that can help diagnose the cause of a lump. For example, you probably know about scans such as mammograms and ultrasound.

You may also have a test called a needle biopsy, where a tiny piece of tissue from the lump is taken for testing under a microscope.

Using scans and a biopsy, doctors can find the cause of almost all breast lumps.

Breast cancer and breast lumps in men

When we talk about breast cancer we almost always talk about women. But, although it’s rare, men can get breast cancer.

About 1 in every 100 people who get breast cancer are men.

Men can get benign breast lumps, too. But this is also rare. When it does happen, it’s usually caused by a condition called gynaecomastia. This happens when a man’s breast tissue starts to grow because of hormone problems.

If you are a man and you find a lump in your chest, see your doctor. As with women, it’s not usually cancer. But you should find out as soon as possible, just in case.

Things that cause benign breast lumps

Many things can cause a lump in your breast that isn’t cancer. Here, we look at the most common ones.

Fibroadenoma

A fibroadenoma is a tumour that is not cancer. A tumour happens when cells begin to grow and multiply in ways they’re not supposed to. This causes a lump to form.

With a malignant tumour (cancer), this new growth spreads into other body tissues and organs, causing serious illness.

But with a benign tumour like a fibroadenoma, the new growth stays where it is and doesn’t spread. This means that it can’t cause any serious problems.

Fibroadenoma is common. About 10 in every 100 women develop a fibroadenoma at some point in their lives.

Doctors used to think that women with fibroadenomas were more likely to get breast cancer. But newer research suggests that this isn’t true.

Phyllodes tumour

Phyllodes tumours are tumours that are usually benign. They can sometimes be malignant (cancerous), but this is rare.

Even when these tumours are malignant, they rarely spread beyond the breast. But most women decide to have treatment, just in case.

Phyllodes tumours can be removed with surgery, but this isn’t always needed. Some women can have treatment with radiation instead.

Fibrocystic breast

Breast cysts are fluid-filled lumps in the breast. Some women have several cysts at a time. This can make your breast feel lumpy, and it can be painful.

For example, you may find that your breast hurts when you move around a lot, or that you need to wear a more supportive bra.

Fibrocystic breasts are fairly common around the menopause. The discomfort usually goes away by itself, but you can take simple painkillers in the meantime.

If your symptoms are severe, your doctor can prescribe other treatments.

It’s rare for breast cysts to develop into cancer, but it can happen. And, as with any lumps or changes in your breasts, it’s always best to see your doctor.

Fat necrosis

Necrosis is what happens when body tissue dies because it doesn’t get enough blood flow.

Areas of fat necrosis in the breast can be caused by several things, including:

• an injury: for example, some women’s breasts are damaged by vehicle seat belts

• damage caused during surgery, and

• damage caused by radiation treatment.

The affected areas can form lumps in your breast that feel like hard scar tissue. Fat necrosis is not dangerous and doesn’t cause cancer. But it can feel uncomfortable.

If you have severe pain, talk to your doctor about possible treatments. Women with large lumps sometimes need to have surgery to remove them. But this is rare.

Breast papilloma

A papilloma is a lump in the breast, usually near the nipple. Women with a breast papilloma often notice bloody discharge from their nipple.

This type of lump is called a papilloma because it grows in a similar way to a wart (warts are caused by a virus called the human papillomavirus), even though breast papillomas aren’t related to warts.

Breast papillomas can sometimes become cancerous over time. So many women have them removed with surgery. But this is not always needed. You can talk to your doctor about whether you need treatment.

Breast abscess

Breast abscesses are common in women who are breastfeeding. They are small local infections caused by blocked or leaking milk ducts in the breast.

They clear up by themselves but they can be uncomfortable. As always, if you are concerned, tell your doctor.

Adenoma

A breast adenoma is similar to a fibroadenoma in some ways. It often happens to women who are breastfeeding or who have recently given birth.

What to look out for

As you can see, there is a long list of things that cause lumps in the breasts that are not cancer. And most breast lumps turn out not to be cancer.

But you should always see your doctor if you notice any changes in your breasts. In particular, see your doctor straight away if you notice changes in your breasts such as:

• a change in the shape or size of a breast

• a lump in a breast

• discharge from one or both nipples

• a change in the texture or colour of the skin of a breast, or

• a rash, or itchy or scaly skin around a nipple.