The accessory mammary gland

The accessory lobe and accessory mammary gland are formed from elements of breast tissue that are located close to the mammary glands themselves: the pectoral muscle area, the subclavian and axillary region.

The accessory lobes do not have nipples, but otherwise behave like a true mammary gland: they are elastic and mobile, increase in size during breastfeeding and are susceptible to the same diseases that may be characteristic of the mammary glands.

The accessory mammary gland has a nipple and a milk duct and is called polymastia in medical circles.

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Causes an accessory mammary gland

There is still no consensus among experts on the reasons for the formation of additional lobes, nipples and mammary glands.

Additional lobes of the mammary gland may appear as a result of genetic disorders, after a sudden hormonal surge (for example, during the period of active puberty).

Accessory glands are considered defects (anomalies) in the development of mammary glands. Normal glands should be located symmetrically, there should be two of them. An additional organ can form either below the normal glands or in atypical areas: on the neck, under the arms, even on the back and genitals.

Most often, the reason for the appearance of such additional elements is a delay in development or incorrect reverse development of the mammary gland at the embryonic level.

Indeed, additional elements of the gland appear as early as the 6th week of embryonic development along the entire length of the milk lines. However, by the 10th week, the extra elements are leveled out, and only a pair of mammary glands remain in the chest area. But in some cases, additional elements do not undergo involution. The exact reasons for this phenomenon have not yet been established.

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Symptoms an accessory mammary gland

An additional lobe of the mammary gland can be painful or painless. Most of all, such anomaly causes aesthetic and psychological inconvenience, which gives rise to a lot of complexes and fears in relation to one's body.

Accessory glands and lobes have a slightly convex volumetric shape in the form of an elastic seal, sometimes with a visual point or nipple. In rare cases, the formation may have the shape of a normal mammary gland. Such an additional organ in most cases is located below the chest or in the armpit area.

A few days before menstruation, the accessory organ increases in volume simultaneously with the increase of the normal breast, the same thing happens during breastfeeding. If there is a nipple, milk may be released from the milk duct of the accessory gland.

This anomaly does not relate to oncology. But the possibility of developing a malignant process in the accessory gland is not excluded, as such cases have been recorded. The risk of malignancy increases if the accessory element is regularly injured by clothing or other accessories.

Accessory lobe of the mammary gland

Normally, the body of the mammary gland has from 15 to 20 lobes, which together have a conical shape. The lobes are located in a circle around the milk duct and are separated from each other by a thin connective tissue layer. Each lobe, in turn, is divided into even smaller lobes, the number of which varies from 30 to 80 in each lobe.

An additional lobe of the mammary gland is an abnormal phenomenon when glandular tissue is found in the chest area, or closer to the subclavian and axillary area. In principle, additional tissue elements themselves are not dangerous, and patients are most concerned, as a rule, with the aesthetic side of the issue. Likewise, an additional lobe does not cause any problems with the breastfeeding procedure.

After lactation, the additional glandular lobe will begin to decrease and will almost disappear over time. There is no need to take any measures in relation to the additional gland: expressing the additional breast can lead to its injury, which is extremely undesirable.

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Accessory mammary gland under the arm

The most typical area of formation of the accessory gland is considered to be the lateral region of the armpit, although in some cases the anomaly can be observed in other areas of the body. Not in all cases the accessory mammary gland is directly connected with the main mammary glands.

An additional mammary gland under the arm is observed in 4-6% of such anomalies: the additional organ develops from the embryonic rudiments along the milk line.

There are eight types of accessory glands, half of which do not contain glandular tissue, but have a full-fledged nipple or areola. Experts are not inclined to classify any of the types of accessory glands as oncology risk factors, although this issue has not yet been thoroughly studied.

Patients with an accessory gland most often agree to surgery due to a certain psychological and physical discomfort that the additional organ element can cause.

An accessory mammary gland on an X-ray image looks like a low-intensity darkening zone, not sharply delimited from the nearest tissues. Such a zone may be surrounded by connective tissue fibers and subcutaneous fat.

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Diagnostics an accessory mammary gland

The visual diagnostic method, which involves examining the breast for the presence of an additional gland and nipples, is not difficult. In some cases, if the additional nipple is not sufficiently developed, it can be confused with a protruding mole.

In obese patients, the accessory lobe should be differentiated from lipoma or cyst.

Additional laboratory and instrumental diagnostic studies may be prescribed when the doctor suspects any pathological process in the abnormal formation. The examination is also carried out before starting treatment of accessory glands.

The examination can begin with a consultation with a mammologist, gynecologist-endocrinologist, or gynecologist-surgeon.

Some additional studies will help to assess the functional capacity and find out if there are any inflammatory or other painful processes. Among such methods, the following can be distinguished:

• Breast ultrasound is a popular study of morphological features of tissues using reflected ultrasound signals. The method makes it possible to detect various tumors, both superficial and deep, with sizes even less than 0.5 cm. Ultrasound allows you to find differences between fibroadenoma, malignant tumor, abscess, cyst and mastitis. The procedure is carried out in the first phase of the menstrual cycle;
• computed tomography is an X-ray computer method that allows you to get not just a snapshot, but a layered image of breast tissue. This method is used mainly to clarify certain details before surgery, to examine nearby lymph nodes, and to determine the depth and growth of a tumor;
• Magnetic resonance imaging of the mammary glands is a method similar to computed tomography, but does not involve X-ray radiation. The MRI procedure is based on the use of magnetic field capabilities. MRI evaluation is sometimes simply necessary when determining the further treatment plan, including surgery;
• Mammography is an X-ray examination of the mammary glands. It is performed in two projections, which allows detecting cystic formations, benign and malignant tumors.

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Treatment an accessory mammary gland

Treatment of such defects as additional lobes of the mammary gland can only be surgical. In principle, it is not necessary to remove such an anomaly if it does not bother the patient and does not cause any inconvenience. Sometimes they limit themselves to monitoring the condition of the additional gland, since such formations are no less susceptible to inflammatory and oncological diseases than normal glands.

Plastic surgery with removal of an additional gland or lobe is recommended in case of an obvious cosmetic defect, pain in the area of the abnormal gland, and detection of pathological processes and functional disorders. An indication for removal of an additional gland is also a burdened heredity, if any of the direct relatives suffered from a malignant process of the breast.

Removal of the accessory lobe of the mammary gland

The surgical intervention is performed by means of correction by liposuction, or by means of removal of the formation with suturing of the skin. The surgical technique may depend on the size and structure of the additional mammary gland.

In the case of a large formation consisting partly of fatty tissue, a 5 mm incision is made and the fatty layer is pumped out.

If this is not enough, the incision is enlarged and elements of glandular tissue are removed. If necessary, part of the skin over the abnormal gland is also removed.

The surgical intervention lasts approximately 1 hour, with intravenous anesthesia. The patient can be discharged on the same day of the operation. The stitches are removed on the seventh or eighth day. There are no special recommendations for the postoperative period.

The operation to remove the accessory gland is usually minimally invasive. The scar after the operation is most often in the armpit area, so it does not cause cosmetic inconvenience. Immediately after the operation, the patient can return to her normal lifestyle.

Forecast

Regardless of whether the patient is bothered by the additional lobe of the mammary gland or not, the anomaly cannot be ignored - any defect in the development of organs can contribute to the development of negative complications and consequences.

If the patient does not intend to undergo radical treatment – removal of the additional lobe of the mammary gland – then, at the very least, she should periodically visit the doctor and undergo preventive ultrasound to monitor the growth and structure of the abnormal formation.

Additional lobes and glands that are located in places subject to constant mechanical damage (friction from clothing, limbs, etc.) are recommended to be removed, since with constant trauma such elements can become malignant (take a malignant course).

After removal of the accessory breast lobe, the prognosis is usually favorable.

An accessory mammary gland is not a rare case, but it requires qualified diagnostics to adequately assess the condition of the formation and determine the need for surgical treatment of the anomaly.

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