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Breast Masses (Breast Lumps)


Lydia Choi

, MD, Karmanos Cancer Center

Reviewed/Revised Jan 2024
Topic Resources

A breast mass (lump) may be discovered by patients incidentally or during breast self-examination or by the clinician during physical examination.

Etiology of Breast Masses

  • Fibrocystic changes

  • Fibroadenomas

Fibrocystic changes (previously, fibrocystic breast disease) refers to nonproliferative lesions, including 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. Fibrocystic changes are the cause of the most commonly reported breast symptoms. Symptoms tend to subside after menopause.

Repeated stimulation by estrogen and progesterone may contribute to the development of 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. Simple fibroadenomas do not appear to have an increased risk of breast cancer. Complex fibroadenomas are associated with a slightly increased risk of breast cancer (1 Etiology reference A breast mass (lump) may be discovered by patients incidentally or during breast self-examination or by the clinician during physical examination. Masses may be painless or painful and are sometimes... read more Etiology reference ). Juvenile fibroadenomas are a variant that occur in adolescents, and unlike fibroadenomas in older women, these fibroadenomas continue to grow over time.

Breast infections (mastitis Mastitis Mastitis is painful inflammation of the breast, usually accompanied by infection. Fever later in the puerperium is frequently due to mastitis. Staphylococcal species are the most common causes... read more ) cause pain, erythema, and swelling; an abscess can produce a discrete mass. Puerperal mastitis, usually due to Staphylococcus aureus, can cause massive inflammation and severe breast pain, sometimes with an abscess. Infections are extremely rare except during the puerperium (postpartum) or after penetrating trauma. They may occur after breast surgery. If infection occurs under other circumstances, an underlying cancer should be sought promptly. Types of benign nonlactational mastitis are periductal mastitis, idiopathic granulomatous mastitis, and tuberculous mastitis (see Extrapulmonary Tuberculosis Extrapulmonary Tuberculosis (TB) Tuberculosis outside the lung usually results from hematogenous dissemination. Sometimes infection directly extends from an adjacent organ. Symptoms vary by site but generally include fever... read more Extrapulmonary Tuberculosis (TB) ); these types occur mainly in young women.

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.

Etiology reference

  • 1. Nassar A, Visscher DW, Degnim AC, et al: Complex fibroadenoma and breast cancer risk: a Mayo Clinic Benign Breast Disease Cohort Study. Breast Cancer Res Treat 153(2):397-405, 2015. doi:10.1007/s10549-015-3535-8

Evaluation of Breast Masses


History of present illness should include how long the mass has been present, whether the size is constant or varies, and whether the mass 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 unilateral, 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 Risk Factors Breast cancers are most often epithelial tumors involving the ducts or lobules. Most patients present with an asymptomatic mass discovered during examination or screening mammography. Diagnosis... read more Risk Factors , 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).

Physical examination

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 Nipple Discharge Nipple discharge can occur in women who are not pregnant or breastfeeding, especially during the reproductive years. Nipple discharge is not necessarily abnormal, even among postmenopausal women... read more Nipple Discharge . Skin changes may include erythema, eczematous appearance, edema, or dimpling (sometimes termed peau d’orange [orange peel]).

The mass is palpated for size, tenderness, consistency (ie, hard or soft, smooth or irregular), borders (well-defined or nondiscrete), 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.

Red flags

Certain findings are of particular concern:

  • Mass fixed to the skin or chest wall

  • Stony hard, irregular mass

  • Skin dimpling

  • Thickened, erythematous skin

  • Bloody or spontaneous nipple discharge

  • Matted or fixed axillary lymph nodes

Interpretation of findings

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, patients require testing to exclude breast cancer more conclusively.


Initially, physicians try to differentiate solid from cystic masses because cysts are rarely cancerous. Typically, ultrasonography is done first. Lesions that appear cystic may be aspirated (eg, when they cause symptoms).

Fluid aspirated from a cyst is sent for cytology if

  • It is turbid or grossly bloody.

  • Minimal fluid is obtained.

  • A mass remains after aspiration.

If these findings are present, mammography followed by imaging-guided core needle biopsy is done.

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.

Solid masses are evaluated with mammography followed by imaging-guided core needle biopsy Breast Cancer Screening and Prevention Breast cancer screening is recommended for all women in the United States, but major medical organizations vary regarding the starting age and frequency of screening (see table ) ( 1, 2). Determining... read more . Surgical biopsy is done if image-guided biopsy is not possible because the lesion is too close to the skin or chest wall, if the patient cannot maintain the position needed for needle biopsy, or if the patient prefers surgical biopsy.

Treatment of Breast Masses

Treatment of a breast mass 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. The American Society of Breast Surgeons recommends that adenomas be excised if they have any of the following features: stromal mitoses, stromal overgrowth, nuclear pleomorphism, fragmentation, or adipose tissue infiltration (1 Treatment reference A breast mass (lump) may be discovered by patients incidentally or during breast self-examination or by the clinician during physical examination. Masses may be painless or painful and are sometimes... read more Treatment reference ). 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 solely because they increase in size.

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.

A galactocele typically resolves after aspiration.

Treatment reference

  • 1. The American Society of Breast Surgeons: Consensus guideline on concordance assessment of image-guided breast biopsies and management of borderline or high-risk lesions; 2016. Accessed December 18, 2023.

Key Points

  • Most breast masses are not cancer.

  • Breast masses are usually evaluated first with ultrasonography.

  • Cystic masses are aspirated and require further evaluation if the fluid is turbid or bloody, minimal fluid is obtained, or the mass does not resolve.

  • Solid masses are evaluated with mammography and biopsy.

Drugs Mentioned In This Article

Drug Name Select Trade
7T Gummy ES, Acephen, Aceta, Actamin, Adult Pain Relief, Anacin Aspirin Free, Aphen, Apra, Children's Acetaminophen, Children's Pain & Fever , Children's Pain Relief, Comtrex Sore Throat Relief, ED-APAP, ElixSure Fever/Pain, Feverall, Genapap, Genebs, Goody's Back & Body Pain, Infantaire, Infants' Acetaminophen, LIQUID PAIN RELIEF, Little Fevers, Little Remedies Infant Fever + Pain Reliever, Mapap, Mapap Arthritis Pain, Mapap Infants, Mapap Junior, M-PAP, Nortemp, Ofirmev, Pain & Fever , Pain and Fever , PAIN RELIEF , PAIN RELIEF Extra Strength, Panadol, PediaCare Children's Fever Reducer/Pain Reliever, PediaCare Children's Smooth Metls Fever Reducer/Pain Reliever, PediaCare Infant's Fever Reducer/Pain Reliever, Pediaphen, PHARBETOL, Plus PHARMA, Q-Pap, Q-Pap Extra Strength, Silapap, Triaminic Fever Reducer and Pain Reliever, Triaminic Infant Fever Reducer and Pain Reliever, Tylenol, Tylenol 8 Hour, Tylenol 8 Hour Arthritis Pain, Tylenol 8 Hour Muscle Aches & Pain, Tylenol Arthritis Pain, Tylenol Children's, Tylenol Children's Pain+Fever, Tylenol CrushableTablet, Tylenol Extra Strength, Tylenol Infants', Tylenol Infants Pain + Fever, Tylenol Junior Strength, Tylenol Pain + Fever, Tylenol Regular Strength, Tylenol Sore Throat, XS No Aspirin, XS Pain Reliever
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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