Gynecomastia is hypertrophy of breast glandular tissue in males. It must be differentiated from pseudogynecomastia, which is increased breast fat, but no enlargement of breast glandular tissue.
During infancy and puberty, enlargement of the male breast is normal (physiologic gynecomastia). Enlargement is usually transient, bilateral, smooth, firm, and symmetrically distributed under the areola; breasts may be tender. Physiologic gynecomastia that develops during puberty usually resolves within about 6 mo to 2 yr. Similar changes may occur during old age and may be unilateral or bilateral. Most of the enlargement is due to proliferation of stroma, not of breast ducts. The mechanism is usually a decrease in androgen effect or an increase in estrogen effect (eg, decrease in androgen production, increase in estrogen production, androgen blockade, displacement of estrogen from sex-hormone binding globulin, androgen receptor defects).
If evaluation reveals no cause for gynecomastia, it is considered idiopathic. The cause may not be found because gynecomastia is physiologic or because there is no longer any evidence of the inciting event.
In infants and boys, the most common cause is:
• Physiologic gynecomastia
In men, the most common causes are:
• Persistent pubertal gynecomastia
• Idiopathic gynecomastia
• Drugs (particularly spironolactone, anabolic steroids, and antiandrogens)
Breast cancer, which is uncommon in males, may cause unilateral breast abnormalities but is rarely confused with gynecomastia.
History: History of present illness should help clarify the duration of breast enlargement, whether secondary sexual characteristics are fully developed, the relationship between onset of gynecomastia and puberty, and the presence of any genital symptoms (eg, decreased libido, erectile dysfunction) and breast symptoms (eg, pain, nipple discharge).
Review of systems should seek symptoms that suggest possible causes, such as
• Weight loss and fatigue (cirrhosis, undernutrition, chronic kidney disease, hyperthyroidism)
• Skin discoloration (chronic kidney disease, cirrhosis)
• Hair loss and frequent infections (undernutrition)
• Fragility fractures (undernutrition, hypogonadism)
• Mood and cognitive changes (hypogonadism)
• Tremor, heat intolerance, and diarrhea (hyperthyroidism)
Past medical history should address disorders that can cause gynecomastia and include a history of all prescribed and OTC drugs.
Physical examination: Complete examination is done, including assessment of vital signs, skin, and general appearance. The neck is examined for goiter. The abdomen is examined for ascites, venous distention, and suspected adrenal masses. Development of secondary sexual characteristics (eg, the penis, pubic hair, and axillary hair) is assessed. The testes are examined for masses or atrophy.
The breasts are examined while patients are recumbent with their hands behind the head. Examiners bring their thumb and forefinger together from opposite sides of the nipple until they meet. Any nipple discharge is noted. Lumps are assessed and characterized in terms of location, consistency, fixation to underlying tissues, and skin changes. The axilla is examined for lymph node involvement in men who have breast lumps.
Red flags: The following findings are of particular concern:
• Localized or eccentric breast swelling, particularly with nipple discharge, fixation to the skin, or hard consistency
• Symptoms or signs of hypogonadism (eg, delayed puberty, testicular atrophy, decreased libido, erectile dysfunction, decreased proportion of lean body mass, loss of visual-spatial abilities)
• Symptoms or signs of hyperthyroidism (eg, tremor, tachycardia, sweating, heat intolerance, weight loss)
• Testicular mass
• Recent onset of painful, tender gynecomastia in an adult
Interpretation of findings: With pseudogynecomastia, the examiner feels no resistance between the thumb and forefinger until they meet at the nipple. In contrast, with gynecomastia, a rim of tissue > 0.5 cm in diameter surrounds the nipple symmetrically and is similar in consistency to the nipple itself. Breast cancer is suggested by swelling with any of the following characteristics:
• Eccentric unilateral location
• Firm or hard consistency
• Fixation to skin or fascia
• Nipple discharge
• Skin dimpling
• Nipple retraction
• Axillary lymph node involvement
Gynecomastia in an adult that is of recent onset and causes pain is more often caused by a hormonal abnormality (eg, tumor, hypogonadism) or drugs. Other examination findings may also be helpful.
Testing: If breast cancer is suspected, mammography should be done. If another disorder is suspected, appropriate testing should be done. Extensive testing is often unnecessary, especially for patients in whom the gynecomastia is chronic and detected only during physical examination. Because hypogonadism is somewhat common with aging, some authorities recommend measuring the serum testosterone level in older men, particularly if other findings suggest hypogonadism. However, in adults with recent onset of painful gynecomastia without a drug or evident pathologic cause, measurement of serum levels of LH, FSH, testosterone, estradiol, and human chorionic gonadotropin (hCG) are recommended. Patients with physiologic or idiopathic gynecomastia are evaluated again in 6 mo.
In most cases, no specific treatment is needed because gynecomastia usually remits spontaneously or disappears after any causative drug (except perhaps anabolic steroids) is stopped or underlying disorder is treated. Some clinicians try tamoxifen 10 mg po bid if pain and tenderness are very troublesome in men or adolescents, but this treatment is not always effective. Tamoxifen may also help prevent gynecomastia in men being treated with high-dose antiandrogen (eg, bicalutamide) therapy for prostate cancer; breast radiation therapy is an alternative. Resolution of gynecomastia is unlikely after 12 mo. Thus, after 12 mo, if cosmetic appearance is unacceptable, surgical removal of excess breast tissue (eg, suction lipectomy alone or with cosmetic surgery) may be used.
• Gynecomastia must be differentiated from increased fat tissue in the breast.
• Gynecomastia is often physiologic or idiopathic.
• A wide variety of drugs can cause gynecomastia.
• Patients should be evaluated for clinically suspected genital or systemic disorders.
A 15-year-old boy comes to the office for a physical examination before going to summer camp. He says that he has a tender "lump" in his right breast that he noticed a couple of months ago. He is very concerned because he is going to a new camp and he is worried that he is going to have to change clothes in front of other boys in his bunk. He thinks that the other boys are going to see it and make fun of his "breast". There are tears streaming down his face as he tells you this. Physical examination shows a 1.5-cm, tender, palpable mass symmetrically distributed beneath the right areola. There is no discharge from the right nipple. The left breast is unremarkable. The remainder of the physical examination shows a small amount of dark, curling pubic hair and open and closed comedones on his cheeks, forehead, and back. The most appropriate next step is to
A. order liver function tests
B. perform ultrasonography of the breast
C. prescribe testosterone to give him a more "masculine" body-type
D. reassure him that this is common and no further testing is indicated
E. refer him for a fine needle aspiration
The correct answer is D. Gynecomastia (puberal hypertrophy) is very common in adolescents during puberty and is frequently asymmetric and tender. It is important to reassure this patient that it affects approximately 50–60% of adolescent boys at around Tanner stage III. It usually regresses before age 20. Surgery is rarely indicated. The open and closed comedones (also known as "blackheads" and "whitehead") are part of acne vulgaris, which is another common problem that affects adolescents.
Evaluation for liver disease (choice A) is unnecessary at this point because gynecomastia is very common during adolescence. He has no other signs of liver disease.
An ultrasound (choice B) is often used to distinguish cystic from solid masses. It is not indicated at this time in this case because this patient most likely has puberal hypertrophy of the breast (gynecomastia).
It is completely inappropriate to prescribe testosterone to give him a more "masculine" body-type (choice C) because testosterone often causes gynecomastia. Testosterone is converted to estradiol in extraglandular tissues and leads to feminization.
Fine needle aspiration (choice E) and mammography are used to evaluate a dominant breast mass or possibly gynecomastia in a patient who is not going through puberty, has a negative drug history, or a rapidly growing, large (>4cm) mass. This patient's gynecomastia is most likely due to puberty, making further work-up too aggressive at this time.
The parents of a 7-year-old boy bring him to you for evaluation. They have noted bilateral breast development. There is no history of exogenous estrogen use. His vital signs are normal, including a regular heart rhythm at a rate of 88. He has otherwise been well and is on no mediations. There is no history of ambiguous genitalia at birth. On examination, the testes are approximately 1 cm each bilaterally. The penis is small. Breast tissue is palpable bilaterally with discernible areola development. There are no abdominal masses. The boy is 40th percentile for height and weight. Which of the following do you recommend?
A. Reassure parents that it is just benign gynecomastia and is probably transient
B. Begin treatment with testosterone enanthate 50 mg IU each month
C. Begin search for estrogen-secreting tumor
D. Obtain surgical consultation for excisional biopsy of breast masses
E. Review the family history for similar occurrences
The answer is C. Begin search for an estrogen-secreting tumor. In contrast to boys in puberty, in which over 30% have at least a transient gynecomastia, breast development in males before puberty causes concern about estrogen exposure, from either an estrogen-secreting tumor (adrenal, testicular, or bronchogenic) or exogenous estrogen exposure. Interesting is that fact that hyperthyroidism is sometimes associated with excess estrogen, but not hypothyroidism. Besides the obvious difference in setting between benign transient gynecomastia and an endocrinologically significant condition (pubertal vs. prepubertal), there may be the question of gynecomastia versus enlarged breast in an obese male. In case of obesity, there is neither palpable breast bud nor particular areola development. Thus, reassurance is inappropriate; treatment with testosterone is premature, as is surgical consultation for excisional biopsy. This condition is associated with no identifiable familiality. Thyroid function is not feasibly an issue in this case.
A 14-year-old boy comes to the office because his breasts have recently become tender and slightly swollen. He is worried that he is undergoing feminization and will grow up to become a “freak.” Upon examination a tender, 2-cm mass is found to be palpable in the subareolar region of both breasts. Which of the following describes the best course of action?
A. Excise the masses by performing a subcutaneous mastectomy.
B. Incise and drain the masses.
C. Treat the masses with topical steroids.
D. Aspirate the masses for culture and cytology.
E. Leave the masses alone.
The patient has gynecomastia, the development of breast tissue in males, which is normal in the neonate, pubertal boy, and elderly male. Increased estrogen stimulation (hyperestrinism) of breast tissue is the common factor in all cases of gynecomastia.
Adolescent gynecomastia is usually bilateral, and the tissue averages 2 to 3 cm in diameter. The breast enlargement is transient and most often subsides within 1 year; as a consequence the gynecomastic breast usually should be left alone (choice E). The boy should be reassured that he is normal and does not have to worry about developing breasts.
However, if the mass is greater than 5 cm or does not regress by 16 to 17 years of age, a subcutaneous mastectomy should be performed (choice A). Incision (choice B), aspiration (choice D), and topical steroids (choice C) are not indicated under any circumstances. Gynecomastia in a postpubertal, adult male younger than 70 to 80 years is not normal and hyperestrinism should be suspected. Hyperestrinism in an adult male is most commonly due to decreased catabolism of estrogen due to liver cirrhosis, most often induced by alcoholism. However, hyperestrinism also can be due to increased synthesis secondary to an adrenal or testicular tumor; increased human chorionic gonadotropin (HCG) from a testicular tumor; the hyperplastic Leydig’s cells in Klinefelter syndrome; decreased androgen activity, which leaves estrogen unopposed (e.g., caused by hypothalamic or pituitary disorders); and by several drugs.