What is Galactocele ( Lactocele )?
A galactocele, also known as a lactocele or a lacteal cyst, is a rare and harmless cyst, or small sac, filled with milk. The name galactocele comes from the Greek words ‘galatea,’ meaning milky white, and ‘-cele,’ meaning pouch. This cyst generally occurs in breastfeeding women and appears as painless round lumps in the breast that can occur on either one or both sides.
Whilst a galactocele can appear anywhere along the so-called “milk line” – the area that extends from the armpit to the groin – they tend to form most often behind the nipple area of the breasts. It’s crucial to make sure that the lump is indeed a galactocele and not another type of breast disease, like a cyst, fibroadenoma, breast abscess, or even breast cancer.
Ultrasound is the best method for diagnosing a galactocele. A procedure called fine-needle aspiration (FNA), where a small needle is used to draw fluid from the lump, is often used as a diagnostic and treatment method. If the fluid is milky, it’s likely the lump is a galactocele.
What Causes Galactocele ( Lactocele )?
A galactocele, a cyst filled with milk, can form in the breast when there are three specific conditions: secretory breast tissue is present, there’s a stimulus for the hormone prolactin, and the breast’s milk ducts are blocked.
Secretory breast tissue is most commonly seen in women in the last trimester of pregnancy, while breastfeeding, and sometimes even after stopping breastfeeding. Essentially, this tissue is responsible for making breast milk due to an influence of certain hormones such as estrogen and progesterone. Interestingly, milk can start being produced as early as the 16th week of pregnancy. There are different factors that can increase the chance of a galactocele forming, including difficulty breastfeeding and situations where breastfeeding is not possible or safe. For example, in cases where the mother is infected with HIV, the child has certain metabolic or anatomical issues, or the mother is taking certain harmful medications.
Interestingly, the use of birth control pills has also been linked to the formation of galactocele due to their effect on breast tissue.
A prolactin trigger is another condition important to form a galactocele. This has been seen even in male infants where the hormone prolactin passes from mother to baby during pregnancy, or in certain medical conditions like pituitary adenomas or hyperprolactinemia that can cause a high level of prolactin in the body.
Ductal obstruction is the third condition required for a galactocele to form. It has been reported that certain breast surgeries, like breast augmentation, can lead to injury and subsequent obstruction of the milk ducts. There have been cases of galactocele reported after such surgeries, even those which use a technique that was meant to minimize risks.
Surprisingly, nerve stimulation during surgery may lead to changes in the brain’s control over the production of prolactin, which in turn increases milk production, leading to a prolactin surge that might contribute to galactocele formation.
However, it’s important to note that galactocele is not related to genetic factors, meaning there isn’t that we currently know any link between genetics and the risk of developing this condition.
Risk Factors and Frequency for Galactocele ( Lactocele )
Benign breast diseases, which are non-cancerous conditions, are often seen in women between their 20s and 50s, with the highest number occurring between their 40s and 50s. This is different from malignant, or cancerous breast conditions, where the risk tends to increase as a woman gets older. The most common symptom of benign breast diseases is a lump in the breast, which accounts for 87% of cases.
One benign breast condition, known as a galactocele, is estimated to occur in 4% of women presenting with benign conditions. It accounts for approximately 4 to 5% of all breast lumps that are classified as category four lesions when a specific tissue test, called a core needle biopsy, is performed. Despite these statistics, galactocele is not usually highlighted in medical literature, likely because it often doesn’t produce symptoms and isn’t harmful.
Signs and Symptoms of Galactocele ( Lactocele )
A galactocele, a condition that can occur in lactating mothers, typically begins as a lump in the breast that slowly grows over time. It usually doesn’t cause any pain or fever. Mothers who are breastfeeding for the first time, are having trouble breastfeeding, or are feeding formula to their babies instead of natural breast milk are more at risk. This is due to incomplete removal of milk from the milk ducts. The risk can also increase if the mother is taking certain medications like metoclopramide and domperidone, which are known to increase milk production. Notably, domperidone is commonly available over-the-counter with proton pump inhibitors, which are often used to treat conditions like acid reflux.
Usually, the main sign of a galactocele is a lump in the breast. This lump can vary in tenderness and is typically firm, distinct, and can be moved easily under the skin. The lump may or may not be accompanied by a milky discharge from the nipple. Unlike many infections or inflammation, there usually are no signs of these conditions with a galactocele. This can give the impression that the lump is a solid tumor, particularly in women of child-bearing age.
Testing for Galactocele ( Lactocele )
For any new noticeable lump in the breast, it’s important that it’s promptly checked out. This usually involves a three-step assessment to determine what it could be. First, a doctor will perform a physical examination, then they will use imaging technology for a closer look, and if needed, they can perform a cytologic or histologic assessment, meaning they’ll examine the cells or tissues in a lab.
The diagnosis of a galactocele, which is a condition common in breastfeeding mothers, can be primarily confirmed through a clinical examination. However, further examinations such as imaging can confirm the diagnosis.
For lactating mothers who usually have dense breasts, an ultrasound is the ideal choice after a clinical examination. This type of imaging can help detect whether the lump is a galactocele by checking if it appears as a clear, well-defined packet with thin, bright walls and some enhancement of the sound waves beyond it.
There may be variations in the appearance of the lesion depending on where it’s located and how long it’s been there:
1. Location:
1. Central: If the cyst is in the center of the breast, it is usually simple and characterized by no compartmentalization or signal in the cyst.
2. Peripheral: If it’s near the edge of the breast, the cyst may have thin separations and appear as several compartments.
2. Duration:
1. Acute: If it’s new and the content of it is still primarily liquid, it appears more uniform with medium-level signals.
2. Chronic: If it’s older and the contents have thickened, it appears mixed with internal fluid divisions and clear fluid bands. Bright spots with sound wave shadowing are also seen. The brightness within it results from the contents which are milk products including about 10% solids, fat, and sloughed-off skin cells.
If a varied signal with irregular borders is noted, this may indicate the formation of an abscess. This condition usually presents with signs like redness, tenderness, and warmth and should be considered in line with these symptoms.
Colour Doppler investigation, which shows blood flow, may be used to further differentiate a complex cyst from more serious conditions like carcinomas or papillomas, where blood flow would be expected. A galactocele should show no blood flow on this test.
In specific circumstances, a mammogram (a type of x-ray) may be used as a problem-solving technique to limit radiation exposure. This can show an unclear or well-outlined mass with high transparency due to the high fat content and water-fat level.
Several different appearances can be observed when looking at galactoceles on mammograms. These depend on the ratio of fat to protein in the breast milk:
1. When the galactocele has high fat compared to protein, the lump appears clear on a mammogram and mimic a lipoma (a fatty lump). This appearance is called a pseudolipoma.
2. If the fat content is low, the fat floats on top of the breast milk in the fluid-filled cyst. This is usually clearer in certain views of the mammogram.
If the densities of the fat and water are mixed because the two have not separated, it may resemble a hamartoma, which contains high viscosity milk. This appearance is called pseudohamartoma.
Treatment Options for Galactocele ( Lactocele )
A galactocele is a collection of milk inside a lump in the breast that usually goes away on its own once a woman stops breastfeeding. The hormonal changes that occur during pregnancy and breastfeeding cause these collections, but they typically resolve once lactation stops.
For lactating women, an ultrasound-guided procedure using a fine needle can help diagnose and treat a galactocele in most cases. This procedure should be done under the cover of antibiotics to protect against infections, primarily staff infections, since they’re the most common causes of breast abscesses. A reoccurrence of the galactocele is unlikely, and breast massage during pregnancy and after childbirth can help prevent it and provide treatment.
If a woman who has had breast augmentation develops chronic overproduction of breast milk causing a galactocele, certain medications like Bromocriptine can be prescribed. These medications work by inhibiting milk secretion, as a decrease in dopamine output in the body is one proposed cause of overproduction of breast milk.
Most prolactinomas, which are benign tumours of the pituitary gland causing an overproduction of the hormone prolactin, are treated with medication alone. Surgery or radiation therapy is recommended for cases that do not respond to medical therapy. Bromocriptine is a commonly preferred medication for this condition.
If the galactocele does not resolve following aspiration, surgical removal may be required. This is particularly true if the galactocele is growing rapidly, if the results of diagnostic tests are inconsistent, or if the lump comes back after complete drainage. These signs could point towards a potential breast cancer risk, and so medical examination of the cells or tissues (cytology or histopathology) is often recommended.
What else can Galactocele ( Lactocele ) be?
There are several possibilities when examining a breast-related issue. It can be any one of the following:
- Breast cyst
- Breast abscess
- Breast carcinoma (cancer)
- Fibrocystic changes (changes in breast tissue)
- Fibroadenomas (noncancerous breast lumps)
- Lactating adenoma (breast tumor while breastfeeding)
- Traumatic fat necrosis (damaged fatty tissues)
- Hematoma (clotted blood outside the blood vessels)
- Hamartoma (a benign, or noncancerous, growth)
What to expect with Galactocele ( Lactocele )
A galactocele is a harmless condition that naturally improves and goes away once breastfeeding stops, without needing any treatment. This means it has a very good outcome. Importantly, there is no reported increase in the risk of developing breast cancer or fibrocystic disease, which is a condition that can cause lumpy or painful breasts, following a galactocele.
Possible Complications When Diagnosed with Galactocele ( Lactocele )
Breast lactation cysts, or galactoceles, typically go away on their own once lactation has ended. However, in rare cases, the cyst can harden, and the milk inside it can form an inspissated cyst and also turn into crystals. This hardened or crystallized galactocele is not easily identifiable through an ultrasound because it doesn’t have the usual characteristics of a galactocele. It can sometimes be wrongly identified as other harmless or solid breast lumps.
A fine needle aspiration (FNA) test will show a white, gritty material. When stained for examination, this material reveals small, distinct purple crystals. A special type of stain called Leishman’s shows differently shaped crystals. There are also amorphous proteinaceous materials seen around these crystals. Emptying a hardened galactocele cannot be achieved by aspiration alone, and it may need to be surgically removed.
A common complication with galactoceles is acute mastitis, a breast infection resulting from unsterile techniques during aspiration or surgical excision. This infection can worsen and result in breast abscesses. These abscesses present with swelling and tenderness in the breast, accompanied by signs of inflammation. The most common bacteria causing this infection is Staphylococcus aureus and Streptococcus species. These germs are commonly found in the nose and throat of nursing infants and cause an infection through any damage in the breast nipple-areola complex. In this stage, the ultrasound shows a complex cyst with thickened walls. Antibiotics and surgical drainage are used as a treatment for these cases. If a breast implant is in place, it may also get infected, requiring the removal of the implant and draining of the abscess.
Lastly, breastfeeding should continue, even in the case of a galactocele, as it promotes drainage. Breast milk fistula, which involves milk leakage, is a rare but possible complication as a result of incomplete surgical removal of the galactocele.
Recovery from Galactocele ( Lactocele )
If you have a non-infected galactocele (a milk-filled cyst in your breast) and it’s treated with a fine-needle aspiration (a procedure where a thin needle is used to withdraw fluid), you can continue breastfeeding right away. Massaging your breast may also help. If for some reason you can’t breastfeed, you’re encouraged to empty your breasts by hand or use a breast pump. Using ice packs and providing support for your breasts can also help. [20]
Preventing Galactocele ( Lactocele )
All new moms and their newborn babies should get care within the first day after birth. It’s important that new moms get help learning the right ways to breastfeed their babies. This is where nurse practitioners, midwives, and breastfeeding specialists come in. They play a crucial role in preventing, detecting early, and giving timely referrals for new moms who might have lumps in their breast. These healthcare professionals are also key in teaching patients and their families about their health.
It’s really important that new moms and their babies have regular check-ups to ensure they are both doing well. Moms should also get advice on the importance of keeping their breast area clean while breastfeeding. There’s no overemphasizing the necessity of educating the moms and taking care of their own health. This can be done through handing out informational leaflets and posters or suggesting educational websites, if they are available.
