Mammary glands in children

From the sixth week of embryonic development, almost simultaneously with such organs as the heart and lungs, the mammary glands of children begin to form. At first, dense epidermal growths appear in the embryonic tissue (mesenchyme), which extend from the armpit to the groin area. Later, these structures turn into acini and remain only in the chest area. And the nipples are formed in the perinatal period (after the 22nd week of gestation) - by the spread of the mesenchyme underlying the areola. In newborns of both sexes, the nipples are located in small depressions and soon after birth, due to the proliferation of the connective tissue surrounding them, they take on a normal appearance. All this is physiology.

However, there are many pathological processes that can cause an age-inappropriate enlargement of the mammary glands in a child, as well as redness or hardening of the mammary glands in children.

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Mammary glands in children of the first year of life

Most full-term babies experience a so-called sexual crisis in the first days of life due to the cessation of the flow of maternal sex hormones into the bloodstream. On the 3rd-4th day after birth, engorgement or swelling of the mammary glands in children occurs, which can increase over the next 5-7 days. The baby's mammary gland may become red, and small amounts of milk-like fluid may appear from the nipples. Doctors also call this phenomenon physiological mastopathy of newborns.

As pediatric neonatologists note, a lump in the mammary glands of children can occur – right under the nipple. The formation is always single, up to 2-3 cm in size. It can disappear in a couple of weeks, or it may not go away for several months while the child is breastfed: some babies have increased sensitivity to the hormone prolactin, which contains breast milk.

Parents need to know that this is not a disease, but a specific reaction of the child's body. It is necessary to consult a doctor, but nothing needs to be treated, you should only carefully observe hygiene. Because its non-observance is fraught with mastitis (inflammation of the mammary gland) of newborns, which can develop into an abscess.

And in this case, the causes of mammary gland diseases in a child during infancy are infection, most often with staphylococci or streptococci, and the development of an inflammatory process that needs to be treated (see below).

Mammary glands in prepubertal children

Enlargement of the mammary glands in a child before puberty, particularly in girls under 8 years of age, is an abnormality. According to doctors, this is premature thelarche, that is, the beginning of development of the mammary glands before girls enter puberty (which begins after 10 years of age). Premature thelarche is considered a benign isolated condition, so to speak, a local process, which consists of the development of the mammary glands without the appearance of other secondary sexual characteristics.

It can be caused by problems with the ovaries (cysts), adrenal glands or thyroid gland (hypothyroidism), as well as the use of exogenous hormones or medications. Thus, several years ago, Turkish researchers (Gazi University, Ankara) found out that long-term use of fennel, used to regulate bowel function in infants and relieve bloating, causes an increase in the mammary glands in the child and can lead to too early breast development in girls under two years of age. The fact is that the biologically active substances of this plant stimulate the synthesis of estrogens.

It should also be taken into account that the asymmetric development of the mammary glands in girls under 12 years of age corresponds to the peculiarities of this process: one gland (usually the left) develops earlier than the second, but, ultimately, the breasts become symmetrical.

According to some data, approximately 4% of girls with premature thelarche have central precocious puberty. What does this mean? This is when the enlargement of the mammary glands in girls begins before the age of 8 and is accompanied by hair growth in the pubic and armpit areas. Today, there are good reasons to believe that one of the key causes of this pathology is mutations in the genes of leptin (Lep) and leptin receptors (Lepr) - a peptide hormone of adipose tissue responsible for regulating energy metabolism in the body. According to research by endocrinologists, an increase in the mammary glands in a child is observed in almost 80% of cases when his body weight exceeds the average age indicator by 9-10 kg.

Causes of breast diseases in children

Experts name the following reasons for diseases of the mammary glands in children, as well as their pathological development:

• damage to the brain system (due to infection, trauma, intracranial neoplasm, or radiation) that inhibits the hypothalamic-pituitary-gonadal axis, which leads to the premature release of gonadotropic hormones - luteinizing hormone (LH) and follicle-stimulating hormone (FSH);
• hypothyroidism;
• prepubertal hypogonadism (decreased testosterone levels in boys due to functional failure of the testicles);
• follicular ovarian cyst;
• germ cell tumors of the ovary;
• congenital adrenal hyperplasia;
• prolactinoma (a pituitary tumor that produces prolactin);
• embryonic tumor of the hypothalamus (hamartoma);
• pineal gland tumor (pinealoma);
• McCune-Albright syndrome (congenital increased production of growth hormone, STH).

The mammary glands of obese children of both sexes are often enlarged; this can result in the formation of a tumor consisting of fat cells surrounded by connective tissue – a lipoma of the mammary gland.

In boys of pubertal age (over 12 years old), an enlargement of the mammary glands is observed, which is called juvenile gynecomastia. Its cause lies in the age-related increase in the production of follicle-stimulating hormone (FSH) by the pituitary gland. This results in a temporary imbalance of sex hormones, which disappears over time.

Pain in the mammary glands of a child, as well as hardening of tissue in the nipple area, can be the result of even the most minor injury.

In adolescent girls, against the background of hormonal instability typical for this age, fibrocystic and hyperplastic changes in the breast may be detected:

• breast cyst in a child (a benign round formation in the form of a cavity with internal contents);
• hyperplasia of the mammary gland in a child - see Hyperplasia of the mammary gland
• fibroadenoma (mobile benign tumor) – see Fibroadenoma of the mammary gland

The prognosis for most benign types of fibrocystic mastopathy is favorable. However, with significant proliferation of epithelial tissues of the mammary gland, there is a risk of malignant degeneration of neoplasia.

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Breast cancer in a child

In pediatric practice, breast cancer in children is diagnosed extremely rarely. Most problems with the mammary glands in childhood are benign mastopathy and many resolve without specific treatment.

However, there is juvenile secretory carcinoma, a rare form of the disease, most often diagnosed in adolescent girls. Secretory carcinoma of the mammary gland is a special variant of invasive ductal cancer, typical for underage patients. It develops slowly in the form of small, poorly defined on ultrasound single or multiple nodular neoplasms (0.5-3.5 cm in size) in the ducts of the mammary glands. The peculiarity of this type of tumors is periodic secretory discharge from tumor cells; microcalcifications may also be present in the neoplasms.

Breast cancer in a child of pubertal age in the form of phyllodes cystosarcoma is also a rare diagnosis. But it is a very aggressive tumor, affecting both the parenchyma of the mammary gland and its skin.

There are other types of cancer that can spread as metastases to breast tissue, such as lymphomas that affect the lymph nodes in the chest and armpits; leukemia, soft tissue sarcomas, neuroblastoma, etc.

The causes of breast diseases in a child in case of detection of oncology are often associated with both hormonal surges of adolescence and with a predisposition inherited from the maternal line, in particular, mutations of the BRCA1 and BRCA2 genes. According to the American National Cancer Institute (NCI), BRCA1 mutations increase the risk of developing breast cancer (and ovarian cancer) by 55-65%, and BRCA2 mutations - by 45%.

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Symptoms of breast diseases in children

Let us briefly list the typical symptoms of breast diseases in children.

Mastitis in newborns is characterized by: enlargement of the mammary gland with a zone of compaction of subcutaneous tissue; hyperemia; soreness; high body temperature (up to +38°C); loss of appetite, gastrointestinal disorders (vomiting, diarrhea) may occur. When an abscess develops, the temperature reaches +39°C, a purulent infiltrate forms in the reddened area, the child is inhibited and refuses to breastfeed.

Juvenile gynecomastia in boys is characterized by: swelling of the mammary glands in children similar to edema, occurring below the nipples - with increased sensitivity of the nipples. And with gynecomastia associated with hypogonadism, painful to the touch seals form in the boy's mammary glands, and there are also symptoms such as underdevelopment of the secondary sexual organs, excess fatty tissue in the upper body, pale skin, lethargy, sleep disorders, etc.

Symptoms of fibrocystic pathologies and hyperplasia of the mammary gland in adolescent girls may manifest as: swelling of the mammary glands after the end of menstruation, a feeling of fullness in the chest, edema and mastalgia (pain of varying intensity), the presence of elastic or harder rounded nodules or elongated (scar) neoplasia in the breast tissue. In fibrous pathologies, formations are formed in the upper quadrant of the gland (closer to the armpit). Larger formations can lead to a change in the shape of the glands or their asymmetry. The skin color in the affected area may change, and liquid discharge is possible from the nipple. In the presence of cysts, which in adolescent girls are localized under the nipple, the skin in the areola area often has a bluish tint.

It should be borne in mind that in many cases these pathologies occur without pronounced symptoms, and neoplasia is discovered completely by accident.

Breast cancer in a child can manifest itself with almost the same symptoms. In addition, discomfort and pain can often be felt in the armpit area, the nipple is slightly drawn into the areola, and the skin on the chest can look like orange peel.

Diagnostics of pathologies of mammary glands in children

Clinical diagnosis of mammary gland pathologies in children is carried out on the basis of an examination, which begins with a physical examination of the child and collection of anamnesis (including family history).

To determine the level of hormones in the blood serum (such as estradiol, prolactin, testosterone, LH, FSH, 17-OPG and DHEA-S, gonadotropin-releasing hormone, somatropin), it is necessary to take a biochemical blood test. The blood is also tested for AFP - a marker of germ cell tumors alpha-fetoprotein and tumor growth markers.

Not only is ultrasound of the child's mammary glands performed, but also ultrasound sonography of the thyroid gland, adrenal glands and pelvic organs. Mammography is not performed on children.

Differential diagnostics of mammary gland pathologies in children is carried out using computed tomography or magnetic resonance imaging of the adrenal glands and brain structures: the pituitary gland, hypothalamus, and pineal body.

In case of fibrocystic and hyperplastic changes in the mammary glands – to exclude oncology – a fine-needle aspiration biopsy of the formation (or axillary lymph node) is performed with histological examination of the obtained biopsy.

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Treatment of mammary gland diseases in children

The same treatment for breast diseases in children is not possible, and therapeutic methods are determined by the specific diagnosis.

Thus, swelling of the mammary glands in children in the first months of life does not require treatment, but in case of purulent mastitis, antibiotics cannot be avoided, and sometimes drainage of the abscess (which is performed by a surgeon in a hospital setting). And the best prevention of mastitis in infants is ideal cleanliness and proper care of the child.

Early development of the mammary gland (thelarche) does not require treatment. However, any changes in the size of girls' mammary glands should be monitored.

For more information on how precocious puberty is treated, read – Precocious Puberty – Treatment

Enlargement of the mammary glands in a boy also requires observation, and if juvenile gynecomastia does not resolve spontaneously within a couple of years after diagnosis, then an endocrinologist - based on the results of a blood hormone test - will prescribe treatment with hormonal drugs and recommend wearing a chest bandage.

In case of excess fatty tissue, its removal (liposuction) can also be used.

Mastopathy in girls during puberty should be treated by a pediatric gynecologist or mammologist. But other specialists can also come to the rescue, since the etiology of cystic formations is associated with the thyroid gland, and hyperplasia of the mammary gland in a child can occur due to neuroendocrine pathologies and disorders of the hypothalamic-pituitary-gonadal system.

In oncology, treatment of mammary gland diseases in children is carried out in the same ways as in adults (surgery, chemotherapy).

Doctors say that if you seek medical help in a timely manner, the prognosis for most mammary gland pathologies in children is positive. However, their prevention has not been developed to date.