Breast Lumps: A Merck Manual of Patient Symptoms podcast
A breast lump may be discovered by patients incidentally or during breast self-examination or by the clinician during routine physical examination. Lumps may be painless or painful and are sometimes accompanied by nipple discharge or skin changes.
Although cancer is the most feared cause, most breast lumps are nonmalignant. The most common causes include
Fibrocystic changes (previously, fibrocystic disease) is a catchall term that refers to mastalgia, breast cysts, and nondescript lumpiness, which may occur in isolation or together; breasts have a nodular and dense texture and are frequently tender when palpated. Fibrocystic changes cause the most commonly reported breast symptoms and have many causes. Most causes are not associated with increased risk of cancer; they include adenosis, ductal ectasia, simple fibroadenoma, fibrosis, mastitis, mild hyperplasia, cysts, and apocrine or squamous metaplasia. Other causes, particularly if fibrocystic changes require biopsy, may slightly increase risk of breast cancer. Fibrocystic changes are more common among women who had early menarche, who had their first live birth at age > 30, or who are nulliparous.
Fibroadenomas are typically painless lumps that feel like small, slippery marbles. They usually develop in young women, often in adolescents, and may be mistaken for cancer, although they are benign and tend to be more circumscribed and mobile. Simple fibroadenoma does not appear to increase risk of breast cancer; complex fibroadenoma may increase risk slightly.
Breast infections (mastitis) causes pain, erythema, and swelling; an abscess can produce adiscrete 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 mo after lactation stops. Such cysts rarely become infected.
Cancers of various types can manifest as a lump. About 5% of patients have pain.
History of present illness should include how long the lump has been present and whether it comes and goes or is painful. Previous occurrence of lumps and the outcome of their evaluation should be queried.
Review of systems should determine whether nipple discharge is present and, if present, 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 2 known breast cancer genes, BRCA1 or BRCA2.
Examination focuses on the breast and adjacent tissue. The breast is inspected for skin changes over the area of the lump and the presence of any nipple discharge. Skin changes include erythema, exaggeration of normal skin markings, and trace edema sometimes termed peau d'orange (orange peel). The lump 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.
Certain findings are of particular concern:
Interpretation of findings
Painful, tender, rubbery lumps in younger women with a history of similar findings 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 lumps because cysts are rarely cancerous. Typically, ultrasonography is done. Lesions that appear cystic are sometimes aspirated, and solid lumps are evaluated with mammography followed by imaging-guided biopsy (see Breast Disorders: Diagnosis). Some physicians evaluate all lumps with needle aspiration; if no fluid is obtained or if aspiration does not eliminate the lump, mammography followed by imaging-guided biopsy is done.
Fluid aspirated from a cyst is sent for cytology only if it is bloody, if minimal fluid is obtained, or if a mass remains after aspiration. Patients are reexamined in 4 to 8 wk. 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 3rd recurrence or persistence of the mass after initial aspiration (even if cytology was negative) requires biopsy.
Treatment is directed at the cause. Fibroadenomas can usually be excised using a local anesthetic, but they frequently recur. After patients have had several fibroadenomas established as benign, they may decide against having subsequent ones excised.
Acetaminophen, NSAIDs, and athletic bras (to reduce trauma) can be used to relieve symptoms of fibrocystic changes. Vitamin E is sometimes used but has not been proved to be effective.
Last full review/revision November 2008 by Victor G. Vogel, MD, MHS