What Can Cause a Hard Lump in the Breast?

You might be worried if you discover a lump in your breast, but lumps aren’t always a sign of a serious condition. Most breast lumps aren’t caused by cancer, especially if you’re under 40 years old and haven’t had breast cancer in the past.

Breasts are made up of many parts, including:

• nerves
• blood vessels
• connective tissue
• glandular tissue
• milk glands
• milk ducts
• fat

Together, these can make breasts feel uneven and lumpy.

Hard breast lumps will feel different from your typical breast tissue. They often have several harmless causes, including:

• hormonal changes during your menstrual cycle
• clogged milk ducts
• infections

Typically, noncancerous lumps will be easy to move and roll between your fingers. Lumps you can’t move and roll with your fingers have a greater chance of being cancerous and are a cause for concern.

Benign breast lumps

A variety of conditions can cause lumps in your breast tissue. Some causes, such as menstrual cycle changes, can create breast lumps that form briefly and go away on their own. Other causes might need medical attention but are not cancer.

Some common and benign reasons for breast lumps include:

• Cysts. A cyst is a fluid-filled sac. They’re generally 1 to 2 inches wide, smooth, and round, with clear, defined edges. Cysts may be tender to the touch, especially during your period. Cysts will often come and go throughout your menstrual cycle. But large or painful cysts might need further medical care.
• Lipomas. A lipoma is a fatty lump that can form in your breast tissue. These lumps are generally painless, soft, and easy to move with your fingers. Lipomas are always benign, but your doctor might order a biopsy to confirm the lump is a lipoma and not cancer.
• Fibroadenoma. These benign lumps are most common during your 20s and 30s, but can occur at any age. A fibroadenoma lump generally will be hard and round. You’ll be able to move the lump with your fingers. Sometimes, your doctor will biopsy or remove fibroadenoma lumps to make sure they’re not cancerous. In many cases, they can be left untreated without causing harm.
• Fibrocystic changes. These changes are caused by hormonal fluctuations and are very common in women ages 30 to 50. They can cause your breasts to feel tender, fibrous, and rubbery. They might also cause fluid-filled cysts to form. Fibrocystic changes often occur in middle age and can sometimes be treated with birth control or dietary changes.
• Fat necrosis. Fat necrosis happens when the fatty tissue of your breast is injured. It can cause round, firm lumps or cysts to form. Fat necrosis lumps sometimes need surgical removal.
• Mastitis. Mastitis is an infection of the breast tissue, such as a milk duct. It’s most common in women who are breastfeeding. Mastitis can cause your breast to be lumpy, swollen, warm, and red, and may give you a fever. In most cases, it can be treated with antibiotics. In some cases, your doctor might want to do a biopsy to make sure your symptoms aren’t caused by cancer.

Precancerous breast lumps

Some breast lumps are caused by conditions that aren’t cancer but still call for medical attention. If these lumps don’t get treatment, they can increase your risk of cancer or even progress into cancerous tumors.

Common types of precancerous breast lumps include:

• Intraductal papillomas. These tumors form in the milk ducts and are usually benign. However, they are associated with an increased risk of cancer. They often cause nipple discharge along with lumps.
• Hyperplasia. Breast hyperplasia can be located in the fatty tissue of your breast (lobular hyperplasia) or the ducts (ductal hyperplasia). It causes lumps that aren’t cancerous, but can become cancerous without treatment. Hyperplasia lumps need to be removed as soon as possible.
• In situ tumors. Just like hyperplasia lumps, in situ tumors can form in the fatty tissue (lobular carcinoma in situ) or ducts (ductal carcinoma in situ). These tumors aren’t invasive and are considered stage 0 cancer. They need to be removed before they can progress to an invasive cancer stage.

Breast cancer lumps

Breast cancer lumps are invasive. They’re caused by atypical breast tissue cells that can grow and spread to the rest of your breast, lymph nodes, and other organs.

Early breast cancer usually doesn’t have any signs or symptoms because of its small size. In these cases, it’s most commonly identified on routine screening tests.

When breast cancer advances, it often first appears as a single, hard, one-sided lump or thick area under your skin with irregular borders. Unlike benign lumps, you generally can’t move a breast cancer lump with your fingers.

Breast cancer lumps usually aren’t tender or painful to the touch. They most often appear in the upper section of your breast in the area toward your armpit. They can also appear in your nipple area or the lower half of your breast.

Other signs that might point to breast cancer include:

• a lump that is irregularly shaped
• a lump with a dimpled or bumpy surface
• a change in the appearance of your nipples
• a change in the texture of your breasts
• a change in the shape of your breasts, including asymmetry
• open wounds that develop on your breasts without any injuries
• nipple discharge
• nipple tenderness
• nipples that are inverted
• swollen glands in your armpits

Men can also experience hard lumps in their breast tissue. Similar to lumps in women’s breast tissue, lumps aren’t necessarily cancer or a serious condition. For example, lipomas and cysts can cause lumps in men’s breast tissue.

Often, hard breast lumps in men are caused by a condition called gynecomastia. This condition causes men’s breast tissue to become enlarged and can cause a lump to form under the nipple. The lump is often tender and can occur in both breasts.

In some cases, this condition is brought on by hormonal imbalances or a medication, but in other cases, no clear cause can be found.

Fortunately, gynecomastia doesn’t cause medical harm, but it can damage the self-confidence and self-esteem of affected men. Treatment depends on the cause, and might include:

• medications
• weight loss
• surgery

Many causes of breast lumps are benign and can even go away on their own. However, it’s always a good idea to have a breast lump checked out by a medical professional.

For more benign lumps, this can mean simply bringing the lump up with your doctor at your next regularly scheduled appointment. For lumps that might be cancer, it’s best to make an appointment right away.

There are several signs to look for that can indicate that a lump may be cancerous. Use them to decide when to seek treatment.

When to bring a lump up at your next physical

Some breast lumps aren’t harmful and can wait to be discussed with your doctor. These include lumps that:

• shrink and grow during your menstrual cycle
• are tender or painful
• can be easily moved with your fingers

It’s best to always trust your instincts when it comes to a breast lump. If your lump meets these criteria, but something doesn’t feel right, make a medical appointment right away. While most breast lumps aren’t cancer, it’s a good idea to get something checked out, especially if you’re concerned about it.

When to make an appointment for a breast lump

If a breast lump could be harmful, make an appointment for a medical professional to evaluate it soon. Don’t wait until your next appointment. Signs it’s a good idea to make an appointment include breast lumps that:

• can’t be moved with your fingers
• grow over time
• don’t cause pain or tenderness
• have bumpy surfaces

When a breast lump is an emergency

A breast lump along with other signs could mean you should seek emergency care. If you have breast cancer that has begun to spread, an appointment can’t wait. It’s best to seek urgent medical care if you have a hard breast lump and:

• you are experiencing bloody nipple discharge
• your nipples have changed appearance or become inverted
• you have a fever
• the glands under your arms are swollen

A lump along with any of these signs doesn’t always mean you have invasive breast cancer or even breast cancer at all. However, because breast cancer is most treatable when it’s caught early, it’s important not to wait.

Again, it’s always best to follow your instincts. If you have a hard lump in your breast and are concerned something is seriously wrong, make an appointment.

Many hard lumps in breast tissue are harmless. They can be caused by hormonal changes and might come and go on their own. These lumps are often easily moved with your fingers and might be tender to the touch. Lumps caused by breast cancer generally don’t cause pain and can’t be easily moved.

It’s a good idea to mention any lump you feel in your breasts to a medical professional. They might want to order a biopsy to find out exactly what it is and get you the best treatment.