The term breast mass is preferred over lump for a palpably discrete area of any size. A breast mass may be discovered by patients incidentally or during breast self-examination or by the clinician during routine physical examination.
Masses may be painless or painful and are sometimes accompanied by nipple discharge or skin changes.
Although breast cancer is the most feared cause, most (about 90%) breast masses are nonmalignant. The most common causes include
Fibrocystic changes (previously, fibrocystic disease) is a catchall term that refers to mastalgia, breast cysts, and nondescript masses (usually in the upper outer part of the breast); these findings may occur in isolation or together. Breasts have a nodular and dense texture and are frequently tender when palpated. The breasts may feel heavy and uncomfortable. Women may feel a burning pain in the breasts. Symptoms tend to subside after menopause.
Fibrocystic changes cause the most commonly reported breast symptoms and have many causes. Repeated stimulation by estrogen and progesterone may contribute to fibrocystic changes, which are more common among women who had early menarche, who had their first live birth at age > 30, or who are nulliparous. Fibrocystic changes are not associated with increased risk of cancer.
Fibroadenomas are typically smooth, rounded, mobile, painless masses; they may be mistaken for cancer. They usually develop in women during their reproductive years and may decrease in size over time. Juvenile fibroadenoma, a variant, occurs in adolescents, and unlike fibroadenomas in older women, these fibroadenomas continue to grow over time. Simple fibroadenoma does not appear to increase risk of breast cancer; complex fibroadenoma may increase risk slightly.
Breast infections (mastitis) cause pain, erythema, and swelling; an abscess can produce a discrete mass. Infections are extremely rare except during the puerperium (postpartum) or after penetrating trauma. They may occur after breast surgery. Puerperal mastitis, usually due to Staphylococcus aureus, can cause massive inflammation and severe breast pain, sometimes with an abscess. If infection occurs under other circumstances, an underlying cancer should be sought promptly.
Galactocele is a round, easily movable milk-filled cyst that usually occurs up to 6 to 10 months after lactation stops. Such cysts rarely become infected.
Cancers of various types can manifest as a mass. About 5% of patients have pain.
History of present illness should include how long the mass has been present and whether it comes and goes or is painful. Previous occurrence of a mass and the outcome of its evaluation should be queried.
Review of systems should determine whether nipple discharge is present and, if present, whether it is spontaneous or only in response to breast manipulation and whether it is clear, milky, or bloody. Symptoms of advanced cancer (eg, weight loss, malaise, bone pain) should be sought.
Past medical history should include risk factors for breast cancer, including previous diagnosis of breast cancer, history of radiation therapy to the chest area before age 30 (eg, for Hodgkin lymphoma). Family history should note breast cancer in a 1st-degree relative (mother, sister, daughter) and, if family history is positive, whether the relative carried one of the inherited gene mutations that predispose to breast cancer (eg, BRCA1, BRCA2).
Examination focuses on the breast and adjacent tissue. The breast is inspected for skin changes over the area of the mass, nipple inversion (retraction), and nipple discharge. Skin changes include erythema, rash, exaggeration of normal skin markings, and trace edema sometimes termed peau d’orange (orange peel).
The mass is palpated for size, tenderness, consistency (ie, hard or soft, smooth or irregular), and mobility (whether it feels freely mobile or fixed to the skin or chest wall).
The axillary, supraclavicular, and infraclavicular areas are palpated for masses and adenopathy.
Painful, tender, rubbery masses in women who have a history of similar findings and who are of reproductive age suggest fibrocystic changes.
Red flag findings suggest cancer. However, the characteristics of benign and malignant lesions, including presence or absence of risk factors, overlap considerably. For this reason and because failure to recognize cancer has serious consequences, most patients require testing to more conclusively exclude breast cancer.
Initially, physicians try to differentiate solid from cystic masses because cysts are rarely cancerous. Typically, ultrasonography is done. Lesions that appear cystic are sometimes aspirated (eg, when they cause symptoms), and solid masses are evaluated with mammography followed by imaging-guided biopsy. Some physicians evaluate all masses with needle aspiration; if no fluid is obtained or if aspiration does not eliminate the mass, mammography followed by imaging-guided biopsy is done.
Fluid aspirated from a cyst is sent for cytology only under the following circumstances:
Patients are reexamined in 4 to 8 weeks. If the cyst is no longer palpable, it is considered benign. If the cyst has recurred, it is reaspirated, and any fluid is sent for cytology regardless of appearance. A third recurrence or persistence of the mass after initial aspiration (even if cytology was negative) requires biopsy.
Treatment of a breast lump is directed at the cause.
A fibroadenoma is usually removed if it grows or causes symptoms. Fibroadenomas can usually be surgically excised or, if < 3 cm, cryoablated after patients are given a local anesthetic, but fibroadenomas frequently recur. Patients who have fibroadenomas that are not excised should be checked periodically for changes. After patients have had several fibroadenomas established as benign, they may decide against having subsequent ones excised. Because juvenile fibroadenomas tend to grow, they should be removed.
Acetaminophen, nonsteroidal anti-inflammatory drugs (NSAIDs), and athletic bras (to reduce trauma) can be used to relieve symptoms of fibrocystic changes. Evening primrose oil may be somewhat effective.