A lump in the breast is a small mass that is typically associated with benign conditions, like a fibroadenoma or a cyst, and usually does not require treatment.

Breast cancer may be suspected if the lump in the breast is associated with malignant characteristics, such as changes to breast size or shape, or if there is a history of breast cancer in the family (particularly in parents).

If you find a lump in one or both of your breasts during a self-examination, it's important that you see your doctor. He or she will likely order an ultrasound or mammogram to determine whether the lump is benign or malignant, and from there, decide the most appropriate treatment.

Common causes

Some of the most common causes of a lump in the breast include:

1. Fibrocystic breast changes

Fibrocystic changes are the most frequent cause of breast lumps and they are related to hormonal changes in a woman's body (e.g. during a period or when undergoing hormonal treatment).

What it feels like: These lumps can be painful and hard, and may just appear in one breast or both. They normally appear a week before the period starts and disappears a week after the period ends.

2. Simple breast cyst

Breast cysts generally occur in pre-menopausal women who are over the age of forty. They are not serious and rarely develop into cancer, so they do not require specific treatment.

What it feels like: They are commonly found in both breasts and can change in size during menstruation. These lumps may also become more painful after consumption of caffeine, tea or chocolate.

3. Fibroadenoma

A fibroadenoma is a type of lump that is frequent in young women between the ages of twenty and forty. It is caused by excessive growth of the glands that produce milk and breast tissue.

Characteristics of the lump: These lumps are round, slightly hard and they are movable with palpation (ie. they are not fixed to just one location). These lumps do not usually cause pain.

4. Lipoma

A lipoma is caused by a build-up of fatty tissue in the breast and it is not serious. It can even be surgically removed if there is a cosmetic concern.

Read more about lipomas and what causes them.

What it feels like:: Lipomas are soft and can be described as small pillows of fat. They are movable with palpation. However, in some cases, lipomas can also be hard, which can be confused with breast cancer.

5. Breast infections

Some breast infections, such as mastitis during pregnancy, can also cause an inflammation of the tissues and ducts inside the breast and cause lumps.

What it feels like: These lumps cause breast pain, especially when pressed, and the skin will typically be red in the location of the lump.

6. Diabetic mastopathy

Diabetic mastopathy is a rare and serious type of mastitis. This inflammation in the breast causes pain, redness and the appearance of one or more lumps in the breast that can be confused with cancer. This disease only appears in people who have diabetes and that take insulin. This condition mainly affects women.

What it feels like: These lumps are hard masses that are painless when they first emerge. They can also be accompanied by blisters and pus.

7. Breast cancer

Breast cancer is a disease that initially starts as a lump in the breast that is accompanied by other breast changes like changes in nipple color and/or shape, discharge leaking from the nipple, breast skin changes, and breast or nipple itchiness.

Read more about the signs of breast cancer and complete our online symptom checker to determine your risk for this condition.

What it feels like: These lumps do not usually cause pain. They are hard and have an irregular shape that is different from the breast tissue around the nodule.

Tests for breast lumps

Ultrasounds and mammograms are the most common tests used to diagnose lumps in the breast. The doctor will often use their own examination (inspection and palpation) combined with imaging results to reach a diagnosis.

The result of a mammogram is standardized using a BI-RADS classification system. Mammogram test results are as follows:

Category 0: test did not manage to diagnose anomalies and other complementary tests will be necessary;
Category 1: normal result, repeat in one year;
Category 2: benign alterations, no risk of cancer, repeat in one year;
Category 3: possible benign alteration, with a 3% risk of cancer, it is recommended you repeat the test in six months time;
Category 4: possible malignant alterations with a 20% risk of cancer, a biopsy will be necessary as well as an anatomopathological examination of the breast tissue;
Category 5: possible malignant alterations with a 95% risk of cancer, and surgery will be necessary to remove the anomaly, and a pre-op biopsy may be necessary;
Category 6: confirmed breast cancer diagnosis.

Breast lumps that are described as hypoechogenic or hypoechoic do not confirm the severity or the malignancy of the nodule. These are just expressions used to communicate lump characteristics.

Treatment options

Lumps in the breast normally do not need any treatment, as most are not detrimental to health and do not increase in size.

However, when the nodule is painful or very large, the gynecologist may recommend taking specific medication or excising the nodule to relieve symptoms.

In cases where the nodule is malignant, treatment should be guided by a multidisciplinary team made up of an oncologist, breast specialist, pathologist and radiation oncologist, who will consider the type of cancer, stage and the patient's general condition.

Breast lumps in men

Breast lumps in men are usually linked to male breast cancer, but they can also be benign. Therefore, if you notice a lump, consult your doctor so that the origin of the lump can be identified.