Breast lumps facts
- Breast lumps can be caused by infections, injuries, non-cancerous growths, and cancer.
- Breast cancer usually causes no pain in the breast. The symptoms of breast cancer include painless breast lumps, nipple discharge, and inflammation of the skin of the breast.
- The chances that a particular breast lump could be cancerous depends on many factors, including past medical history, physical examination, as well as genetic and other risk factors.
- The only way to be certain that a lump is not cancerous is to have a tissue sampling (biopsy). There are several ways to do the biopsy. The treatment of a breast lump depends on its cause.
What are causes of breast lumps?
There are many causes of breast lumps. Some of these causes are harmless, while others can be painful and/or dangerous. Causes of breast lumps include infections, injuries, non-cancerous growths, and cancer.
Breast cancer is the second leading cause of cancer-related deaths in women in the United States. Currently, death rates from breast cancer are declining. The decline in death rates may be due to a combination of earlier detection and better screening as well as improved treatments. While most breast lumps are harmless (benign), every breast lump should be evaluated by a doctor to exclude or establish a diagnosis of cancer.
Picture of the anatomy of the breast
Breast Cancer Symptoms
Breast cancer may not cause signs and symptoms, so this is one reason that screening mammograms are essential. When symptoms do occur, the most common symptom is a mass or lump in the breast. Other symptoms that can occur are nipple discharge or redness, changes in the skin of the breast (such as dimpling or an orange-peel appearance), and swelling of part of the breast.
Infections that cause breast lumps
Inflammation of the breast tissue is known as mastitis. Mastitis may occur in women who are breastfeeding a baby (lactating). When the skin of the nipple (areola) is injured or cracked, which may occur with nursing, bacteria can enter the damaged area and cause infections. In a breastfeeding woman, a hard area commonly thought of as a "clogged milk duct" can form. Sometimes, certain treatments (see below) can prevent the painful, hard area from developing into an actual breast infection. Infections can either be a deep pocket of pus, in which the infection looks like it is growing down into the breast (an abscess), or a wider area of skin redness that spreads out (cellulitis). Body piercing in the nipple area increases the risk of breast infections, and these may be particularly difficult to treat.
Injuries that cause breast lumps
If a breast is injured by trauma, tiny blood vessels can rupture to cause an area of localized bleeding (hematoma) that can be felt as a lump. Trauma to the breast can damage the fat cells in the breast tissue, a condition called fat necrosis. The injury can also form a lump in the breast. These types of lumps that follow a significant trauma are not cancerous. Fat necrosis can also occur at the site of a previous breast biopsy.
Non-cancerous growths that cause breast lumps
- Fibroadenomas are benign (not cancerous) growths and are very common. These growths most commonly occur in women 30 to 35 years old, but can also occur in women under 30 years of age. Fibroadenomas are solid, firm tumors that are usually painless or only slightly tender. They sometimes grow quickly in teenagers or during pregnancy.
- Breast cysts are fluid-filled, sacs within the breast tissue and are benign. They are very common, especially over the age of 35. These cysts often vary in size during the menstrual cycle and may be tender.
- Fibrocystic changes are characterized by breasts that are lumpy with many irregularities in the breast tissue itself. Fibrocystic breasts seem to occur when a woman's breasts are overly sensitive to fluctuating hormone levels. Women with fibrocystic changes may have pain and/or lumps.
What are the symptoms of breast cancer?
The symptoms of breast cancer include painless breast lumps, nipple discharge, and inflammation (redness) of the skin of the breast. Sometimes breast cancer may not cause any signs or symptoms.
Breast cancer frequently causes no pain in the breast. Although women often worry about breast pain, most women with breast pain do not have breast cancer.
Nipple discharge that occurs without the nipple being touched can be caused by benign (non-cancerous) growths. Examples of these growths are intraductal papillomas (non-cancerous growths that protrude into the milk ducts) and dilated areas of milk ducts (ductal ectasia). Nipple discharge can also be caused by cancer of the breast tissue. Because nipple discharge can be a sign of cancer, it needs to be evaluated by a doctor.
Skin changes on the breast, including redness and warmth, can sometimes be a sign of breast cancer. A form of breast cancer that commonly causes these signs of inflammation is Paget's disease of the breast. However, most inflammation or rashes on the breast are not due to cancer. They may be caused by benign problems such as nipple eczema or a fungal infection. Still, any breast rashes should be evaluated by a doctor. Areas that are especially scaly and red, particularly if they are persistent, or if there is also nipple discharge, are often sampled (biopsied) to rule out cancer.
What determines breast cancer risk?
The chances that a particular breast lump could be cancerous depends on many factors, including a woman's past medical history, her physical examination, and results of radiological tests (e.g. mammograms and ultrasounds). Some of the most important risk factors are outlined below.
Age is the biggest risk factor for breast cancer. In other words, most cases of breast cancer occur due to the fact that the risk of breast cancer increases with age. Most women with breast cancer do not have a history of breast cancer. A woman who has had a prior breast cancer or who has a family history of breast cancer is certainly at risk herself, especially if multiple family members are involved, the cases occurred at a young age, or if the cancer involved both breasts of a single family member.
Women who have received radiation therapy to the chest area as treatment for another cancer have a significantly increased risk for breast cancer.
About 5% to 10% of breast cancer cases have been shown to be related to inherited gene changes (mutations). The most common mutations are those of the BRCA1 and BRCA2 genes, although other genetic mutations may also lead to breast cancers.
Abnormal findings on previous breast biopsies
The finding of certain conditions on previous breast biopsies can also increase the risk for developing breast cancer. Pre-cancerous growths and growths noted on a breast biopsy that represent an increased risk for the development of breast cancer include the following:
- Ductal carcinoma-in-situ (DCIS) is an uncontrolled growth of cells that has not spread beyond the milk duct where it is located. DCIS consists of cancer cells that have not invaded other tissues. Therefore, DCIS is an early stage of breast cancer and is the most common type of noninvasive breast cancer. DCIS is not life-threatening, but must be treated. Women with DCIS have an increased risk for developing a recurrence of the cancer or for development of a new cancer in either breast.
- Lobular carcinoma-in-situ (LCIS) is considered to be a condition in which abnormal cells are confined to the lobules in the breast (the glands that produce milk). Unlike DCIS, LCIS is not considered to have a high probability of becoming a cancer, but it is a sign of risk for that breast or the opposite breast for developing a cancer. Therefore, women with LCIS have a greater chance of developing breast cancer in either breast.
- Proliferative disease of the breast is a benign condition, but it can be a signal that breast cancer may develop in the future. Ductal hyperplasia (the overgrowth of normal cells within the breast ducts) and atypical hyperplasia (overgrowth of abnormal cells in the ducts or lobules that is not serious or extensive enough to qualify as DCIS or LCIS) are examples of conditions that increase the overall risk for developing breast cancer. Not surprisingly, women with atypical hyperplasia have a higher risk than do those with simple ductal hyperplasia (without atypia).
Women with DCIS, LCIS, atypical hyperplasia, or proliferative disease are at even higher risk of developing breast cancer if they have a history of breast cancer in the family.
How are breast lumps evaluated?
A manual examination of the breast is an important screening method for detecting cancer, and it is the first step in the evaluation of a breast lump. Unfortunately, the manual examination of the breast is not precise. However, if a mass can be felt manually, it is important to estimate the location of the mass so that the mammogram and/or other diagnostic examinations can focus on that particular area. A doctor also inspects any suspicious skin changes that may be a sign of breast cancer. Since the manual examination can miss breast cancer, mammography is also an important screening tool.
Women with a breast lump need to have a mammogram of both breasts. A mammogram is estimated to be able to detect about 90% of breast cancers. This means that about 10% of breast cancers are missed by mammography. Therefore, if a woman or her physician feels a lump and the mammogram is normal, further studies or biopsies are carried out to rule out cancer. Sometimes, a certain pattern of calcium deposits appears on the mammogram that makes the doctor suspicious of cancer. In these cases, it is often recommended that a biopsy be taken that is guided by mammogram images to be sure the correct area is sampled.
Ultrasound is useful in the evaluation of breast lumps. It can distinguish between a cyst, which is filled with fluid and a solid lump (which may or may not be cancerous). The first step in the evaluation of a breast lump is to determine whether it is a cyst or solid mass. This is best accomplished by performing an ultrasound examination. In a young woman, where a benign cyst is anticipated and, the ultrasound is confirmatory, she may not require any procedures or biopsies. If it is unclear on the ultrasound whether the lump is enitrely cystic in nature, a further evaluation is usually recommended.
Magnetic resonance imaging (MRI) is becoming more widely used in the evaluation of breast lumps because it is particularly sensitive to small abnormalities in breast tissue. MRI is a special radiology technique designed to image internal structures of the body using magnetism, radio waves, and a computer to produce the images of body structures. Cancers generally have a greater blood supply than non-cancerous growths. The images obtained from an MRI may help determine whether a particular area is cancerous as the MRI exhibits greater contrast in those areas with an increased blood supply. In most cases, MRI is performed if results of mammography and ultrasound evaluations are not conclusive.
MRI also has limitations. For example, MRI cannot detect the presence of calcium deposits, which can be identified by mammography and may be a sign of cancer.
How can a woman be certain that a lump is not cancer?
The only one way to be certain that a lump is not cancerous is to have a tissue sampling (biopsy). There are several ways to perform the biopsy.
Types of biopsy studies inlcude:
- Fine needle aspiration (FNA)
- Core needle biopsy
- Excisional biopsy
Fine needle aspiration is similar to a blood test in that a needle is inserted into the mass and fluid is withdrawn. The fluid and cells are examined by a pathologist for signs suggesting malignancy.
For some patients, a core needle biopsy may be indicated. In this procedure, a hollow needle is inserted into the suspicious area, and a core of tissue is removed through the needle.
To determine the correct location to sample by either method, the lump can either be felt. If it cannot be located in this manner. The FNA or core biopsy may be done during an ultrasound examination or mammogram. FNA of a benign cyst may remove the fluid contents of the cyst and cause the mass to disappear or markedly decrease in size.
If no fluid can be aspirated, and the mass is solid, then a direct tissue sampling must be performed. Tissue sampling using either a core needle biopsy or an excisional biopsy (removal of all or a portion of the abnormal area in a surgical procedure). The excisional biopsy is the best method of making an accurate diagnosis. It is typically done in the operating room using either local or general anesthesia.
How are breast lumps treated?
- A breast infection (mastitis) in a breastfeeding woman is treated with warm compresses and antibiotics.
- A convenient and effective way of applying heat treatment is to wet some washcloths and put them in the microwave briefly to warm them.
- Hot showers are also helpful.
- During heat treatment, the infected area can be massaged.
- After heat treatment, which helps open up the milk ducts, either nursing the baby or using a breast pump can help relieve the swelling and pain. Contrary to common myth, nursing the baby or using a breast pump is a critical part of the treatment because it helps decrease the chance of the infection progressing.
If the area actually looks red or fails to get better with heat, massage, and nursing, a doctor should be consulted for consideration of antibiotics. If untreated, mastitis can quickly progress and develop into a severe infection. Whether a woman is pregnant or not, she needs to see a doctor if the area does not return completely to normal with treatment in order to rule out more unusual types of infections. Cellulitis needs to be treated with antibiotics and frequent follow-ups with the doctor.
- An abscess of the breast often needs to be drained by a doctor because antibiotics alone cannot adequately treat an abscess.
- Fibroadenomas are usually removed because they may otherwise be difficult to distinguish from cancer.
- Breast pain (mastodynia) is a common problem. As long as no mass can be felt by the doctor or patient, and no breast lump is seen on a mammogram or ultrasound, breast pain is often concluded to be a normal condition. It is often thought that this pain is caused by natural hormonal fluctuations. If the discomfort is particularly acute and interferes excessively with a woman's life, oral contraceptives or other medications can be helpful, especially if the pain is worse around the time of the menstrual cycles.
- Fibrocystic changes do not require medication or surgery. Often, a baseline mammogram is done. Then, no further treatment is needed unless a new lump arises, in which case an evaluation with a mammogram and possibly ultrasound is necessary.
- Breast cancer requires urgent treatment. Treatment depends on the type of cancer detected, its size, and its location.
Medically reviewed by Wayne Blocker, MD; Board Certified Obstetrics and Gynecology
American Cancer Society. Non-cancerous breast conditions.
National Cancer Institute. Breast cancer.