• Clinical science

Benign breast conditions


Benign breast conditions are a diverse group of lesions including congenital anomalies (e.g., supernumerary nipples), fat necrosis, mastitis, fibrocystic changes, gynecomastia, and neoplasms such as fibroadenoma, phyllodes tumor, and intraductal papilloma. Fibrocystic changes constitute the most common benign lesion of the breast, and, like the rest of these lesions, primarily affect women between the third and fifth decades of life. Although benign breast conditions may cause symptoms that mimic breast cancer, the majority of these lesions do not increase the risk of malignant disease. Diagnosis is usually made by ultrasound and mammogram, but in some cases biopsy is required. Because of the benign character of these conditions, treatment does not generally involve surgical procedures.


Nonneoplastic lesions Benign breast neoplasms
Fibrocystic changes Mastitis Fat necrosis Galactocele Gynecomastia Fibroadenoma Phyllodes tumor Intraductal papilloma
  • Most common benign lesion of the breast
  • More frequent in nursing mothers
  • < 3% of all breast lesions
  • Peak incidence: 50 years
  • Most common benign breast lesion in lactating women
  • Frequently occurring after cessation of breast-feeding
  • Most common breast mass in women < 35 years
  • Peak incidence
    • Solitary lesions: ∼ 48 years
    • Multiple lesions: ∼ 41 years
Clinical features
  • Painless smooth, mobile, tender mass
  • Firm, concentric, sometimes tender mass at the nipple areolar complex in a male
  • Solitary, well-defined, non-tender, rubbery and mobile mass
  • Painless, smooth, multinodular lump
  • Variable growth rate
  • Generally > 3 cm
  • Clinical
  • Mainly clinical
  • Mammogram (in doubtful cases)
  • Ultrasound and mammogram
  • Core needle biopsy
  • Core needle biopsy
  • In nursing mothers: frequent emptying of the breast
  • Analgesics and cold compresses
  • Antibiotics
  • Unnecessary
  • Only required if cysts are bothering
  • Only required in persistent cases
  • Medical therapy: testosterone replacement or tamoxifen
  • Surgery (subcutaneous mastectomy)
  • Treatment of the underlying cause
  • Regular check-ups
  • Surgical excision
  • Surgical excision


Fibrocystic changes

  • Definition: benign changes characterized by the formation of fibrotic and/or cystic tissue
  • Epidemiology
    • Most common benign lesion of the breast
    • Up to 50% of women are affected during their lifetime.
  • Etiology: unknown
  • Clinical features
  • Diagnosis
    • Physical exam
    • First-line: ultrasound and mammogram
      • Ultrasound: findings range from normal appearance to focal regions of thick parenchyma +/- cysts
      • Mammogram (not recommended for women < 30 years): round or oval masses with clear borders +/- dispersed calcifications
    • Fine-needle aspiration (after imaging confirms a cystic lesion): indicated if the patient is symptomatic and/or requests the procedure
    • Biopsy: confirms diagnosis if imaging is inconclusive
      • Findings vary and include: stromal fibrosis, cysts, papillary apocrine changes, mild epithelial hyperplasia or calcifications
  • Treatment
    • General approach
      • If symptoms are mild, treatment is not required.
      • In case of severe symptoms: oral contraceptives, tamoxifen or progesterone
      • Fine-needle aspiration or surgery: in the case of a cyst causing severe pain or if desired by the patient
        • Reevaluate the cyst after 4–6 weeks
      • Detailed approach
        • Nonproliferative lesions/proliferative lesions without atypia: pharmacotherapy
          • Progestogen replacement therapy
          • Administration of antiestrogen
          • Last resort: combination of prolactin secretion inhibitor (e.g., bromocriptine) and gonadotropin inhibitor
        • Proliferative lesions with atypia: surgery
          • Frequent monitoring with annual mammogram and ultrasound
          • Detection of abnormalities
            • Excision of the nodular changes
            • Subcutaneous mastectomy with nipple preservation
  • Prognosis: : These lesions are nonproliferative and therefore do not increase the risk of cancer.



  • Definition: inflammation of the breast parenchyma that is frequently seen in nursing mothers two to four weeks postpartum
  • Epidemiology
    • Incidence: up to 10% of nursing mothers (particularly 2–4 weeks postpartum)
    • Incidence of periductal mastitis : 5–9% of non-lactating women
  • Etiology
  • Pathophysiology
    • Most frequently in women with nipple fissures , prolonged breast engorgement (e.g., because of overproduction of milk , or insufficient milk drainage (e.g., infrequent feeding, quick weaning, illness in either the baby or mother)
    • Bacteria located in the nostril and throat of the infant or on the skin of the mother enter milk ducts during breastfeeding → pathogen flourishes in stagnant milk → tissue inflammation
    • The pathophysiology of periductal mastitis is not well known, but smoking causes inflammatory damage to subareolar ducts, with tissue necrosis and secondary infection.
  • Clinical features
  • Diagnosis
    • Clinical diagnosis
    • Breast milk cultures or imaging may be required if there is no response to initial treatment.
  • Treatment

A fluctuant mass may indicate a breast abscess.

Patients with mastitis should continue breastfeeding to reduce the risk of a breast abscess!


Fat necrosis of the breast

  • Definition: nonsuppurative inflammatory lesion affecting breast adipose tissue
  • Etiology: trauma
  • Epidemiology
    • Incidence: < 3% of all breast lesions
    • Peak incidence: 50 years
  • Clinical features: irregularly defined and dense breast mass (generally periareolar) causing skin retraction, erythema, or ecchymosis
  • Diagnosis:
    • Mammogram and/or ultrasound: fluid-filled cyst
      • Also on mammogram: coarse rim calcification
    • If any suspicious or inconclusive imaging findings → perform biopsy
  • Treatment: unnecessary


Benign breast neoplasms


  • Definition: : benign breast tumor with fibrous and glandular tissue
  • Etiology: unknown, but a hormonal relationship has been established (growth may occur in parallel to increasing estrogen, e.g., during pregnancy or before menstruation)
  • Epidemiology
    • The leading cause of breast tumor in women < 35 years of age
    • Peak incidence: 15–35 years
  • Clinical features: mostly solitary : , well-defined, non-tender, rubbery and mobile mass
  • Diagnosis
    • Ultrasound: well-defined mass
    • Mammogram: well-defined mass with possibly popcorn-like calcifications
    • If imaging is inconclusive: fine-needle aspiration showing fibrous and glandular tissue
  • Treatment: regular check-ups

Phyllodes tumor

  • Definition: rare fibroepithelial tumor with histology similar to that of fibroadenoma
  • Etiology: unknown
  • Epidemiology
    • 1% of all breast tumors
    • Most commonly benign
    • Peak incidence: 40–50 years
  • Clinical features
    • Painless, smooth, multinodular lump in the breast
    • Variable growth rate: may grow slowly over many years, rapidly, or have a biphasic growth pattern
    • Average size 4–7 cm
  • Diagnosis
  • Treatment
    • Surgical excision
    • In case of recurrence: total mastectomy
  • Prognosis
    • Benign tumors after excision are associated with an excellent prognosis.
    • Lesions with malignant histology may recur and metastasize.

Intraductal papilloma

  • Definition: solitary or multiple benign lesions that arise from the epithelium of breast ducts
  • Etiology: unknown
  • Epidemiology
    • Peak incidence: 40–50 years
      • Solitary lesions: ∼ 48 years
      • Multiple lesions: ∼ 41 years
  • Clinical features
    • Solitary lesions (also known as central papilloma)
    • Multiple lesions (also known as peripheral papilloma)
      • Usually asymptomatic but may rarely cause nipple discharge
      • Peripheral lesions; smaller than solitary papilloma
  • Diagnosis
    • If lesion is palpable: Core needle biopsy is confirmatory and rules out malignancy
    • Otherwise: Ductogram : nonspecific findings such as ectasia and filling defects
  • Treatment: surgical excision of the affected duct
  • Prognosis: generally excellent



Types and pathophysiology
Physiological gynecomastia
Pathological gynecomastia
Idiopathic gynecomastia
  • Up to 25% of patients


Congenital anomalies of the breast

The mammary ridge regresses in the 7th–8th week of embryonal development. Disorders during this stage of development may lead to the following anomalies: