Gynaecomastia

Definition | Aetiology | Pathophysiology | Risk Factors | Signs and Symptoms | Investigations | Management | References

Definition

Gynaecomastia is the benign enlargement of male breast tissue, resulting from an imbalance between the actions of oestrogen and androgens on breast tissue. It can occur at any age but is most common during puberty, in middle-aged, and older men.

Aetiology

Gynaecomastia can be caused by various factors, including:

• Physiological Changes: Hormonal changes during puberty, ageing, or neonatal periods.
• Medications: Certain drugs such as anti-androgens, anabolic steroids, antipsychotics, antidepressants, and some cardiovascular drugs (e.g., spironolactone).
• Underlying Medical Conditions: Conditions such as liver cirrhosis, hyperthyroidism, hypogonadism, kidney failure, and tumours (particularly those secreting oestrogen or HCG).
• Substance Use: Alcohol, cannabis, and anabolic steroids can contribute to the development of gynaecomastia.
• Idiopathic: In some cases, no specific cause is identified.

Pathophysiology

Gynaecomastia results from an imbalance between oestrogen, which stimulates breast tissue growth, and androgens, which inhibit it. This imbalance can occur due to increased oestrogen production, decreased androgen levels, or increased sensitivity of breast tissue to oestrogen. The condition is characterised by the proliferation of glandular tissue, leading to breast enlargement.

Risk Factors

• Age: Most common during puberty and in older men.
• Use of medications known to cause gynaecomastia.
• Chronic medical conditions, such as liver or kidney disease.
• Substance abuse, particularly alcohol and anabolic steroids.
• Obesity, which can lead to increased peripheral conversion of androgens to oestrogen.

Signs and Symptoms

• Enlargement of one or both breasts, which may be symmetrical or asymmetrical.
• Tenderness or sensitivity in the breast tissue.
• Palpable, firm glandular tissue beneath the nipple.
• In some cases, nipple discharge may occur, though this is less common.

Investigations

• Clinical Examination: Assessment of breast tissue to differentiate between glandular and fatty tissue. Examination of the testes and secondary sexual characteristics is also important.
• Blood Tests: Hormonal assays, including testosterone, oestradiol, LH, FSH, prolactin, and thyroid function tests, to identify underlying endocrine disorders.
• Ultrasound: May be used to evaluate breast tissue, particularly if a mass or asymmetry is detected. Testicular ultrasound may be indicated if a testicular tumour is suspected.
• Mammography: Indicated if there is concern about male breast cancer, particularly in the presence of suspicious features such as a hard, immovable mass, nipple retraction, or skin changes.

Management

• Primary Care:
  • Reassurance: Provide reassurance that gynaecomastia is a benign condition, particularly in pubertal cases, where it often resolves spontaneously within 6 months to 2 years.
  • Medication Review: Discontinue or switch any medications contributing to gynaecomastia if possible.
  • Monitoring: Regular follow-up and monitoring for changes in breast size or symptoms.
  • Referral to Breast Clinic: Referral is recommended for further evaluation and management, especially if there are concerns about underlying pathology or if the gynaecomastia is persistent and symptomatic.
• Specialist Care:
  • Medical Therapy: Medications such as tamoxifen or raloxifene (selective oestrogen receptor modulators) may be used to reduce breast size in persistent cases.
  • Surgical Intervention: In cases of significant breast enlargement, persistent pain, or psychological distress, surgical options such as liposuction or mastectomy may be considered.
  • Treatment of Underlying Conditions: Addressing any underlying endocrine or systemic disorders contributing to gynaecomastia.

References

1. NHS (2024) Gynaecomastia: Causes, Symptoms, and Treatment. Available at: https://www.nhs.uk/conditions/gynaecomastia/ (Accessed: 24 June 2024).
2. National Institute for Health and Care Excellence (2024) Gynaecomastia: Assessment and Management. Available at: https://cks.nice.org.uk/topics/gynaecomastia/ (Accessed: 24 June 2024).
3. British Medical Journal (2024) Management of Gynaecomastia. Available at: https://www.bmj.com/content/350/bmj.h4500 (Accessed: 24 June 2024).
4. American Academy of Family Physicians (2024) Diagnosis and Management of Gynaecomastia. Available at: https://www.aafp.org/afp/2024/0624/p4500.html (Accessed: 24 June 2024).

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