Gynecomastia - Symptoms, Causes, Images, and Treatment Options

Diseases

Highlights & Basics

Key Highlights

Gynecomastia is the proliferation of benign male glandular breast tissue. It may be unilateral or bilateral, painful, or asymptomatic.
Gynecomastia results from excessive estrogen action or deficient testosterone action on breast glandular tissue.
Physiologic gynecomastia occurs in the newborn period, during puberty, and with aging and obesity.
Many drugs, environmental exposures, illnesses, and some genetic conditions increase the risk for gynecomastia. Treatment may improve gynecomastia, especially if it is of recent onset.
Most cases require no specific treatment. Therapies for persistent pain or psychological distress include anti-estrogen therapy, androgen replacement if proven testosterone deficiency, or surgery (liposuction or mammoplasty).

Histology: gynecomastia; clusters of ducts, halos of edema, fibrous background; 5X magnification

From the collection of Catherine B. Niewoehner, MD

Quick Reference

History & Exam
- Key Factors
- Other Factors
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Diagnostics Tests
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Treatment Options
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Definition

Epidemiology

Etiology

Pathophysiology

Images

Histology: gynecomastia; clusters of ducts, halos of edema, fibrous background; 5X magnification
Patient with gynecomastia
Hormones involved in male breast development
Histology: normal male breast; rare, isolated ducts; no lobules; 10X magnification
Histology: normal female breast; many ducts; prominent lobules; 10X magnification
Gynecomastia evaluation
Histology: breast cancer; nests of malignant ductal carcinoma invading tissue; 10X magnification

Citations

Key Articles

Kanakis GA, Nordkap L, Bang AK, et al. EAA clinical practice guidelines-gynecomastia evaluation and management. Andrology. 2019 Nov;7(6):778-93.[Abstract][Full Text]
Bromley HL, Dave R, Lord N, et al. Gynaecomastia: when and why to refer to specialist care. Br J Gen Pract. 2021 Apr;71(705):185-8.[Abstract][Full Text]
Bhasin S, Brito JP, Cunningham GR, et al. Testosterone therapy in men with hypogonadism: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab. 2018 May 1;103(5):1715-44.[Abstract][Full Text]
American College of Radiology. ACR appropriateness criteria: evaluation of the symptomatic male breast. 2018 [internet publication].[Full Text]
Mulhall JP, Trost LW, Brannigan RE, et al. Evaluation and management of testosterone deficiency: AUA guideline. J Urol. 2018 Aug;200(2):423-32.[Abstract][Full Text]

Referenced Articles

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