What are the causes of breast swelling in males?

Male breast swelling can have many causes, with gynaecomastia being one of the most common. Gynaecomastia is the benign enlargement of breast gland tissue in males, often prompting visits to doctors due to cosmetic concerns or discomfort.

The most severe potential cause of breast swelling is breast cancer.

Other causes include:

Pseudogynaecomastia: This condition involves an increase in fatty tissue without actual glandular proliferation and is often linked to weight gain.

Lipoma: A benign tumour made of fatty tissue that usually feels soft and can move slightly under the skin.

Sebaceous cyst: A small, non-cancerous bump beneath the skin forms when the sebaceous gland is blocked.

Dermoid cyst: This unusual growth is typically benign and contains structures such as hair, fluid, teeth, or skin glands.

Fat necrosis: This occurs when fatty breast tissue is damaged, typically by injury, resulting in firm, round lumps.

Hematoma: A collection of blood outside of blood vessels, usually caused by an injury, presenting as a bruise or a firm mass.

How would you differentiate the possible causes?

In true gynaecomastia, the tissue that can be felt is rubbery or firm and is located evenly around the nipple-areolar complex. It's often found on both sides but can also occur on just one side. Features of breast cancer typically include a hard, fixed, painless mass that's usually on one side. It might also come with skin puckering, nipple pulling inward, nipple discharge, and swollen lymph nodes under the arms. Although male breast cancer is mostly unilateral, bilateral cases (affecting both breasts) are rare, making up about 1.5% of all male breast cancers, and cases where both breasts develop cancer simultaneously are even rarer, less than 0.5%.

Sometimes, it can be hard to tell the difference between gynaecomastia and breast cancer just by feeling the area. You should always consult your primary healthcare provider.

What are the common underlying causes of gynaecomastia?

Gynaecomastia arises from an imbalance in the ratio of free oestrogen to free testosterone, which can be due to various physiological and non-physiological factors.

Medication use is the most common non-physiological cause, but other factors also need consideration. When assessing gynaecomastia, it's important to take a detailed medication history and look for signs of various conditions such as:

Cirrhosis: Indicated by jaundice, fluid accumulation in the abdomen (ascites), and itching (pruritus).

Malnutrition: Can affect hormone levels and tissue health.

Chronic renal failure: Symptoms include swelling (oedema) and fatigue.

Hyperthyroidism: Characterised by weight loss, heart palpitations, and a fine tremor.

Hypogonadism: Symptoms include erectile dysfunction, decreased muscle mass, and testicular atrophy.

Testicular tumours: Notable for a palpable mass in the testicles.

Adrenal tumours: These may present with an abdominal mass.

Medications:

Cardiovascular: Spironolactone, Digoxin, Amiodarone.

Hormonal: TRT, Anti-androgens (e.g., bicalutamide, flutamide), Oestrogens, Gonadotropin-releasing hormone (GnRH) agonists, 5-alpha reductase inhibitors (e.g., finasteride, dutasteride).

Antimicrobials: Ketoconazole, Metronidazole.

Psychoactive: Haloperidol, Diazepam, Tricyclic antidepressants.

Chemotherapy: Alkylating agents, Methotrexate.

Recreational: Alcohol, Tetrahydrocannabinol (THC; marijuana), Anabolic steroids.

Idiopathic and Other Causes:

Conditions such as cirrhosis, malnutrition, hypogonadism, tumours secreting hCG or oestrogen/oestrogen precursors (e.g., testicular or adrenal tumours), chronic renal failure, and hyperthyroidism.

This information is for educational purposes only and should not replace professional medical advice, diagnosis, or treatment. Individual health conditions and treatment responses can vary. Always consult your healthcare provider for advice tailored to your specific health needs. If you have any questions about a medical condition or treatment, seek advice from your doctor or a qualified health professional before starting any new healthcare regimen.

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