Breast Abscesses and Masses

Updated: Apr 13, 2017
  • Author: Andrew C Miller, MD; Chief Editor: Jeter (Jay) Pritchard Taylor, III, MD  more...
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Breast masses are broadly classified as benign or malignant. Common causes of a benign breast mass include fibrocystic disease, fibroadenoma (see the image below), intraductal papilloma, and abscess. Malignant breast disease encompasses many histologic types that include, but are not limited to, infiltrating ductal or lobular carcinoma, in situ ductal or lobular carcinoma, and inflammatory carcinoma. The main concern of many women presenting with a breast mass is the likelihood of cancer. Reassuringly, most breast masses are benign.

Ultrasonogram demonstrates a hypoechoic mass with Ultrasonogram demonstrates a hypoechoic mass with smooth, partially lobulated margins typical of a fibroadenoma.

See Breast Lumps in Young Women: Diagnostic Approaches, a Critical Images slideshow, to help identify and manage palpable breast lumps in young women.

Breast infections are divided into lactational and nonlactational infections. This division is also referred to as puerperal versus nonpuerperal when the process is not associated with pregnancy. The process may be confined to the skin overlying the breast, or it may result from an underlying lesion (eg, sebaceous cyst), as in hidradenitis suppurativa. [1, 2, 3, 4]



The mammary glands arise along the milk lines that extend along the anterior surface of the body from the axilla to the groin. During puberty, pituitary and ovarian hormonal influences stimulate female breast enlargement, primarily owing to accumulation of adipocytes. Each breast contains approximately 15-25 glandular units know as breast lobules, which are demarcated by Cooper ligaments. Each lobule is composed of a tubuloalveolar gland and adipose tissue. Each lobule drains into the lactiferous duct, which subsequently empties onto the surface of the nipple. Multiple lactiferous ducts converge to form one ampulla, which traverses the nipple to open at the apex. [5]

Below the nipple surface, lactiferous ducts form large dilations called lactiferous sinuses, which act as milk reservoirs during lactation. [6] When the lactiferous duct lining undergoes epidermalization, keratin production may cause plugging of the duct, resulting in abscess formation. [7, 8] This may explain the high recurrence rate (an estimated 39%-50%) of breast abscesses in patients treated with standard incision and drainage, as this technique does not address the basic mechanism by which breast abscesses are thought to occur.

Postpartum mastitis is a localized cellulitis caused by bacterial invasion through an irritated or fissured nipple. It typically occurs after the second postpartum week and may be precipitated by milk stasis. [9] There is usually a history of a cracked nipple or skin abrasion. Staphylococcus aureus is the most common organism responsible, but Staphylococcus epidermidis and streptococci are occasionally isolated. Drainage of milk from the affected segment should be encouraged and is best achieved by continuing breastfeeding or use of a breast pump. [3, 8, 4]

Nonlactating infections may be divided into central (periareolar) and peripheral breast lesions. Periareolar infections consist of active inflammation around nondilated subareolar breast ducts—a condition termed periductal mastitis. Peripheral nonlactating breast abscesses are less common than periareolar abscesses and are often associated with an underlying condition such as diabetes, rheumatoid arthritis, steroid treatment, granulomatous lobular mastitis, and trauma. [1, 10, 11] Primary skin infections of the breast (cellulitis or abscess) most commonly affect the skin of the lower half of the breast and often recur in women who are overweight, have large breasts, or have poor personal hygiene. [3]

Breast masses can involve any of the tissues that make up the breast, including overlying skin, ducts, lobules, and connective tissues. Fibrocystic disease, the most common breast mass in women, is found in 60%-90% of breasts during routine autopsy. Fibroadenoma, the most common benign tumor, typically affects women younger than 30 years and accounts for 91% of all solid breast masses in females younger than 19 years. [5] Infiltrating ductal carcinoma is the most common malignant tumor; however, inflammatory carcinoma is the most aggressive and carries the worst prognosis.




United States

After skin cancer, breast cancer is the most commonly diagnosed cancer in women. It accounts for approximately 1 in 4 cancers diagnosed in US women. [12]

Breast infections occur in as many as 10%-33% of lactating women. [13, 14]

Lactational mastitis is seen in approximately 2%-3% of lactating women, [6, 15, 4] and breast abscess may develop in 5%-11% of women with mastitis. [15, 4]


Breast mass

Morbidity and mortality depends on etiology.

Approximately 1 in 28 women (3.6%) die of breast cancer. In 2009, approximately 40,170 women were expected to die from breast cancer, second only to lung cancer. [12]

Despite significant differences in sociodemographic and clinical characteristics, overall and disease-free survival rates are similar for men and women with breast cancer. [16, 17]

Associated morbidity may include scarring, disfigurement, lymphedema, and significant psychologic stress.

Breast abscess

Recurrent or chronic infections, pain, and scarring are causes of morbidity.

Mastitis is usually seen in lactating women, but the presence in a nonlactating woman should spur evaluation for an inflammatory carcinoma, newly onset diabetes, infection withMycobacterium tuberculosis, and other idiopathic causes. [3, 11]

Abscess formation complicates postpartum mastitis in fewer than 10% of cases.

Neonatal mastitis usually occurs in term or near-term infants, is twice as common in females, and progresses to development of a breast abscess in approximately 50% of cases. [18, 19, 5]


African American women have a higher incidence of breast cancer before age 40 years and are more likely to die of breast cancer at every age.

White women have a higher incidence of breast cancer than African American women after age 40 years. [20]

African American women have been variably reported to have an increased incidence of developing a primary breast abscess. [21, 22]


Approximately 99% of breast cancers are found in women.

Up to 1% of breast cancers occur in men, but numbers have been increasing. [16] Men with changes in breast size should undergo as aggressive of a diagnostic workup as women. [18, 19, 23, 24]


Fibroadenoma, a benign condition, is the most common cause of breast mass in women younger than 35 years. [5]

Women aged 40 years or older account for more than 95% of new breast cancer diagnoses and 97% of breast cancer deaths.

The median age at breast cancer diagnosis is 61 years.

Breast infections most commonly affect women aged 18-50 years. [3]

Nonpuerperal breast masses encompass a wider range of ages, from the late second to eighth decade of life. Peak incidence is often in the fourth decade of life. Ninety-five percent of these infections occur in women. [8]

Puerperal breast abscesses and mastitis are commonly found in women of childbearing age (mean age of 32 years). [1]

Access to care

Women who reside in rural settings may be more likely to present with a more advanced cancer stage than women in urban settings. This may partly result from the availability of and access to effective screening tools and primary care. [25]