Gynecomastia: Description, Causes and Risk Factors:
: Excessive development of the male mammary glands, due mainly to ductal proliferation with periductal edema; frequently secondary to increased estrogen levels, but mild gynecomastia may occur in normal adolescence.
Gynecomastia, a benign enlargement of the male breast due to proliferation of the gland, is a common clinical condition. It may be an incidental finding on routine examination or may present as an acute unilateral or bilateral painful tender mass beneath or as a progressive painless enlargement of the breast. In 75% of the cases, it is bilateral. The tissue could be as small as 1 cm or as large as a female breast. To be visible, the breast must be 2 cm or more. Type 1 (pubertal gynecomastia) is defined as enlargment less than 3-4 cm ; type 2 as enlargment greater than 3-4 cm (pubertal macromastia). Rarely nipple discharge will occur ; there could be mild discomfort during certain activities.
The breast tissues of both sexes appear histologically identical at birth and remain relatively quiescent during childhood, undergoing further differentiation at the time of puberty. In the majority of males, transient proliferation of the ducts and surrounding mesenchymal tissue takes place during the period of rapid sexual maturation, followed by involution and ultimately atrophy of the ducts. In contrast, the breast ductal and periductal tissues in females continue to enlarge and develop terminal acini, which require both estrogen and progesterone.
Since estrogens stimulate breast tissue whereas androgens antagonize these effects, gynecomastia has long been considered the result of an imbalance between these hormones. The transition from the prepubertal to the postpubertal state is accompanied by a 30-fold increase in the concentration of testosterone, with only a 3-fold increase in estrogen levels. Therefore, a relative imbalance between serum estrogen and androgen levels may exist during a portion of the pubertal process and may result in gynecomastia. Alterations in the ratio of estrogen to androgen have been found in patients with gynecomastia in association with medications, adrenal and testicular neoplasms, Klinefelter's syndrome, thyrotoxicosis, cirrhosis, primary hypogonadism, malnutrition, and aging.
Gynecomastia would be expected to occur if the breast tissue of some men and boys had an enhanced sensitivity to normal circulating levels of estrogen. Indeed, increased aromatase activity has been found in pubic skin fibroblasts derived from patients with isolated gynecomastia, suggesting that aromatization of androgens to estrogens within breast tissue may be responsible for idiopathic gynecomastia. It has also been suggested that patients with protracted neonatal gynecomastia may be more susceptible to persistent pubertal gynecomastia, supporting the concept that breast glandular tissue is inherently more sensitive to estrogenic stimulation in some boys than in others. However, to date, studies of estrogen and progesterone receptors in pubertal macromastia have not been conclusive.
Considering the high prevalence of gynecomastia, it may coexist with many disorders without there being a clear causal relation:
Neoplasms (adrenal tumors, seminome, leydig's cell tumor, hepatoma, etc.).
- Chronic diseases: Rheumatic fever, renal, neurologic, pulmonary, liver disease.
- Primary testicular failure: radiation, chemotherapy, orchitis, trauma, leukemia, hemophilia, etc.
- Endocrine disorders: hyperthyroidism, congenital adrenal hyperplasia.
Gynecomastia is the most common reason for male breast evaluation. The condition is common in infancy and adolescence, as well as in middle-aged to older adult males. One estimate is that 60-90% of infants have transient gynecomastia due to the high estrogen state of pregnancy.
The next peak of occurrence is during puberty, with a prevalence ranging from 4-69%. Some reports have shown a transient increase in estradiol concentration at the onset of puberty in boys who develop gynecomastia. Pubertal gynecomastia usually has an onset in boys aged 10-12 years. It generally regresses within 18 months, and persistence is uncommon in men older than 17 years. The third peak occurs in older men, with a prevalence of 24-65%.
Many cases of gynecomastia resolve without treatment, and medical treatment is effective in reducing gynecomastia in many cases. For severe cases or cases in which the breast tissue has become scarred, surgical techniques can help restore normal appearance. Typically, gynecomastia is not associated with long-term problems.
The primary symptom of this is enlargement of the male breasts. As mentioned before, this is the enlargement of glandular tissue
rather than fatty tissue. It is typically symmetrical in location with regard to the nipple and may have a rubbery or firm feel. Gynecomastia usually occurs on both sides but can be unilateral in some cases. The enlargement may be greater on one side even if both sides are involved. Tenderness and sensitivity may be present, although there is typically no severe pain.
The most important distinction with this is differentiation from male breast cancer, which accounts for about 1% of overall cases of breast cancer. Cancer is usually confined to one side, is not necessarily centered around the nipple, feels hard or firm, and can be associated with dimpling of the skin, retraction of the nipple, nipple discharge
, and enlargement of the underarm (axillary) lymph nodes.
Your doctor will ask you questions about your medical and drug history and what health conditions run in your family. The doctor will also do a physical examination that may include careful evaluation of your breast tissue, abdomen and genitals.
Initial tests to determine the cause of your gynecomastia may include:
You may need further testing depending on your initial test results, including:
- Computerized tomography (CT) scans.
- Magnetic resonance imaging (MRI) scans.
- Testicular ultrasounds.
- Tissue biopsies.
Most patients with gynecomastia require no therapy other than the removal of any identified cause. Specific treatment of the enlarged breast tissue is indicated if the gynecomastia causes sufficient pain, embarrassment, or emotional discomfort to interfere with the patient's daily life.
Chemical treatment with clomiphen (estrogen antagonist), danazol (antigonadotropic), tamoxifen (antiestrogen) and dihydrotestosterone have been attempted and their efficacy remains to be proven.
Before one considers surgery, it is important to keep in mind that gynecomastia has a high rate of spontaneous regression. Two thirds of type 1 gynecomastia resolved within two years and 90% within three years.
NOTE: The above information is for processing purpose. The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition.
DISCLAIMER: This information should not substitute for seeking responsible, professional medical care.