A swelling or lump produced in any part of the body due to abnormal growth of tissue is known as a tumor. A growth that is found within the breast tissue is known as a breast tumor. It may be non-cancerous (benign) or cancerous (malignant). Although the detection of a breast tumor may be alarming for a woman because of the fear of breast cancer, most tumors of the breast are found to be non-cancerous. Nevertheless a thorough investigation is necessary to rule out malignancy.
Regular self breast examination is encouraged from the age of 20 in order for women to become accompanied to the feel and appearance of a healthy breast. This will help to bring to her notice any changes in the breasts that do not seem normal. Subsequent medical evaluation may help to detect breast cancer at an early stage, which can give positive results with treatment. Breast tumors are more common in women and are very rarely be found in men.
Anatomy and Physiology of the Breast
Each breast contains 15 to 20 lobes, which are further divided into lobules. The breast is made up mainly of fatty tissue and milk glands. The lactiferous ducts or milk ducts carry milk from the glands to the nipples during breastfeeding. The milk glands and ducts vary in size and number according to need, increasing during lactation. The anatomy is discussed in detail under female breast.
The breast also contains other structures such as fibrous connective tissue, blood vessels, lymph vessels, lymph nodes and nerves. The breast does not contain any muscle fibers. It lies over the muscle in the chest known as the pectoralis major. Tumors developing within the breast may be composed of any of these tissues, which also react to hormone levels at different stages in a woman’s life. Read more on female hormones. A breast tumor may be unilateral (in one breast) or bilateral (in both breasts). It may be either benign or malignant.
Types of Benign Breast Tumors
Benign breast tumors are usually soft in consistency and mobile (not fixed). These are slow-growing masses with a clearly demarcated margin or may be encapsulated therefore its removal is fairly easy. Benign breast tumors rarely recur after removal. Spread to distant sites or metastasis is not seen with benign tumors.
Benign breast tumor may be of the following types :
Fibrocystic Breast Disease
It is also known as fibroadenosis. In some women, fibrocystic changes in the breast occur due to hormonal fluctuation. The lumps produced may be hard or rubbery and are often painful. An increase in the lump size may occur just prior to onset of periods. Fibroadenosis presents as a lumpy, irregular breast due to thickening of the breast tissue. This is most often seen in women of child-bearing age or in women approaching menopause. Fibroadenosis may be unilateral or bilateral.
This is the most common type of benign breast tumor seen in women. It usually gives rise to a round, solid, painless tumor in the breast with a rubbery consistency. The lump is well-defined and mobile and is often referred to as a ‘breast mouse’. It usually occurs in young women.
A breast lipoma grows from the fatty tissue of the breast and is enclosed within a fibrous capsule. It is usually felt as a soft, round, painless breast tumor.
These are small fluid-filled sacs, which may be present in both breasts. More than one cyst may be present in a breast. Cysts may increase in size or become more painful at the time of menstruation.
A galactocele or milk cyst may form during lactation as a result of clogging of the milk ducts.
An infected breast cyst or galactocele may lead to a breast abscess. It is a walled of area containing accumulated pus.
This is a very rare condition which may develop as a result of damage to a ventriculoperitoneal (VP) shunt during a mammogram or a breast augmentation procedure.
This is a breast infection and inflammation occurs most commonly during lactation and may give rise to an inflammatory lump in the breast.
Trauma to the Breast
An injury to the breast tissue may result in fat necrosis, which may produce a firm, round, painless mass in the breast.
This is a well-circumscribed, soft and painless breast tumor which may be mistaken for a fibroadenoma. It contains varying amounts of fat, epithelial, and fibrous tissue and needs to be differentiated from a lipoma.
Toughened silicone implants following breast augmentation procedure or leaking implants may present as a breast tumor. This is known as a pseudolump of the breast. Scar tissue formation after breast surgery may also result in pseudolumps of the breast.
This condition may develop due to fibrocystic changes in the lobes of the breast. The enlarged lobe may be distorted by scar-like fibrous tissue, giving the appearance of a tumor. Though benign, this condition is associated with an increased risk of breast cancer.
This is a painless tumor occurring in the connective tissue of the breast. Also known as cystosarcoma phyllodes, this breast tumor is usually benign and is felt as a large, well-defined, firm but mobile growth. Malignancy may occur in some cases.
Intraductal papillomas may be felt as small tumors behind or near the areola. It is a growth in the lining of the milk ducts near the nipple and usually occurs in perimenopausal women. A watery or blood stained discharge from the nipple is a common finding of an intraductal papilloma, therefore breast cancer should be excluded.
Lymph Node Swelling
Enlarged lymph nodes in the axilla (armpit) near the breasts may look like breast tumors. Matted lymph nodes may indicate metastasis from breast cancer or from cancer in other parts of the body.
Malignant Breast Tumors
Malignant tumors, on the other hand, have irregular margins and tend to grow uncontrollably. It presents as a firm to hard, painless growths in the early stages. It is most often found in the upper and outer quadrant of the breast and in the region behind the nipple and areola. In the late stages of the disease, these masses may be fixed to the surrounding tissue. The skin over the breast may show puckering or dimpling, often referred to as the “peau de orange” sign due to its similarity to the skin of an orange. Malignant tumors easily invade neighboring tissues and spread to distant sites such as the brain, lungs, and bone.
Diagnosis of Breast Tumors
A breast tumor is usually detected by a self breast examination, during examination by a medical professional, by a routine mammography, or by ultrasonography. The main concern after detecting a breast tumor is to determine whether the tumor is benign or malignant.
History is very important, with special emphasis on pain, nipple discharge, any injury to the breast, and any recent noticeable changes in the breast. Hormones or other medication being taken should be noted. A proper history can identify risk factors for breast cancer. A thorough clinical breast examination is necessary to look for all features that may indicate breast cancer. Examination of both breasts should be done.
Tests for Breast Tumors
- Mammogram of both breasts are necessary if not already done. A mammogram can detect most breast cancers. In case of a normal mammogram despite the presence of a mass, further tests such as a biopsy may be done to rule out breast cancer.
- Biopsy of the lump and examination of the tissue under the microscope. A biopsy can confirm or rule out cancer. A fine needle aspiration cytology (FNAC) or core-needle biopsy may be conducted to take a sample of breast tissue. Excisional biopsy may be done in case of suspicious breast tumors.
- Needle aspiration in case of a cyst and examination of the fluid under a microscope.
- Magnetic resonance imaging (MRI) may be especially useful for diagnosis of breast tumor in certain cases, such as in a woman with silicone implants.
- Breast ultrasound can help to differentiate solid from cystic tumors and can guide biopsy procedures. It is often more effective than mammography in detecting a tumor in women with dense breast tissue.
- Microscopic examination of the nipple discharge.