What is Mammary Duct Ectasia?
Mammary duct ectasia (MDE) is a condition that causes inflammation in the large ducts, or milk ducts, of the breast. This affects the nipple and the area around it, called the areola. In MDE, the tubes that carry milk in the breast, known as the lactiferous ducts, become unusually wide and twisted because of changes inside them and loss of a component called elastin in the duct walls. This also causes inflammation and fibrosis, or thickening, around the ducts.
Common symptoms of MDE include sometimes painful nipple discharge that can be of various colors, such as white, green/black, or grey, and pain or tenderness in the nipple and areola. Other symptoms can include a nipple that is pulled inwards, or you might feel a lump in the breast. However, it’s worth noting that in many cases, MDE comes with no apparent symptoms.
MDE can sometimes masquerade as more severe conditions, like breast cancer, or other harmless conditions like mastitis, which is a breast infection.
The symptoms of MDE are quite similar to another benign, or non-cancerous, inflammatory condition called periductal mastitis. This one generally affects the nipple-areola area more and occurs mostly in people who smoke. At times, the two conditions can look so much like each other that doctors cannot tell them apart just by examining the patient. The final diagnosis might only be possible after examining tissue samples from the affected duct and nearby area under the microscope. [1]
What Causes Mammary Duct Ectasia?
Scientists are still unsure about the exact cause of this disease. Some think it might simply be a part of getting older, related to gradual changes in the fatty tissue near the duct system, but this doesn’t explain why the illness sometimes appears in children and young adults. Having been pregnant, breastfeeding, and having a history of abortion inconsistently relate to the development of this disease.
What we do know from studying the tissue under a microscope is that the disease often involves clogs in the lactiferous duct system, which transport milk in the breasts. These clogs, caused by thick secretions and cell debris, cause the ducts to widen. But scientists are still figuring out what triggers the disease in the first place.
Risk Factors and Frequency for Mammary Duct Ectasia
The exact number of cases for this abnormality isn’t known. It mainly affects women aged 45 to 55 who are going through menopause, but it’s also been seen in infants, teenagers, and males. Smokers, and those born with inverted or otherwise malformationed nipples, are more likely to have this condition.
Signs and Symptoms of Mammary Duct Ectasia
Mammary duct ectasia (MDE) often doesn’t present any noticeable symptoms. Sometimes, changes in breast texture may occur, and it often becomes noticeable when a nipple discharge appears. Nipple discharge is one of the most common reasons people go to breast clinics, right after breast pain and discovering a lump. Out of all women, 80% will experience a nipple discharge in their lifetime, which is benign in most cases. MDE is also benign and results in this discharge in 6% to 59% of cases.
The discharge related to MDE can be quite variable, varying in thickness, color, and consistency. It’s generally seen in one duct of one breast, but can occur in both. If it’s seen in both breasts, it might be due to a condition called fibroadenocystic disease. While diagnosing MDE can be tricky due to its variable features, pathologic nipple discharge is typically defined as being uni-lateral, spontaneous, and emanating from a single duct.
Diagnosis involves asking about the frequency, amount, and color of the discharge, and whether it’s spontaneous or triggered, as well as whether it’s coming from one or more ducts. Ideally, doctors can examine the discharge during the consultation, possibly with a magnifying tool.
MDE can sometimes result in small tender masses around the nipple with redness due to filled and dilated ducts. When physicians press on these masses, they may observe a discharge from one duct opening. In severe cases, this could cause the nipple to invert. If it gets infected, it could result in a subareolar infection or abscess and this may get confused with other conditions such periductal mastitis or inflammatory carcinoma. In such cases, it’s usually effective to follow a closely-monitored antibiotic regimen.
If infections recur or there’s scarring from previous treatments, more fibrosis forms in the nipple-areola complex, potentially causing nipple distortion or retraction. Newly appearing nipple retraction is often thoroughly investigated, especially in patients with no prior medical history. Also, in case malignancy is suspected, a biopsy should be done to rule out carcinoma.
For a complete examination, doctors must assess both breasts and axillae to look for any lumps or swollen lymph nodes, paying particular attention to the nipple-areola complex. If an infection is present, a swollen and tender axillary lymph node may be found.
It’s essential to note that MDE is very rare in babies and children. Though it can cause nipple discharge, which usually is bloody. This condition should not be mixed with the physiologic nipple discharge due to maternal hormonal exposure. In children, MDE generally resolves itself within two weeks. If the discharge continues for several months, or if a mass other than MDE is located, a biopsy might be necessary.
Testing for Mammary Duct Ectasia
If your doctor suspects that you have a problem with your breasts, they will use a three-step approach to diagnose you. This approach includes a physical check-up, medical imaging like X-rays or scans, and a needle biopsy which involves taking a small tissue sample from your breast with a needle.
The imaging tests that your doctor might use include a mammogram, ultrasound, CT scan, MRI or other tests such as a galactogram or duct endoscopy. Younger women, under 35, typically have an ultrasound, while mammography – with or without ultrasound – is normally used for women above 35. MRI and sometimes CT scans can be used for any age group, particularly when the results of the other tests are unclear. If there’s something suspicious, further tissue confirmation may be required.
If a patient has symptoms indicating MDE (Mammary Duct Ectasia), a condition where the milk ducts in the breast widen and thicken, a mammogram may not be necessary for diagnosis. However, for those without symptoms, a mammogram can reveal features like speck like deposits of calcium (microcalcifications), mass formations, nipple retraction, duct dilatation, and rarely a speculated looking mass.
An ultrasound is generally recommended for all cases of nipple discharge, a common symptom of MDE. The ultrasound can show widened mammary ducts, masses near the areola, solid masses, and abscesses.
An MRI may be used if the ultrasound or mammography reveals a mass that might be cancerous. While MRI’s aren’t vastly better than ultrasound at diagnosing MDE, they can provide additional useful information. For example, an MRI can show thickened walls of the duct and other subtle differences that might help diagnose MDE.
Galactography is a test used in young patients with nipple discharge after having an ultrasound. This test involves injecting a contrast material into the milk duct and taking images. This test could confirm the presence of MDE and saves the patient from needing further invasive procedures.
NDC (Nipple Discharge Cytology) is a non-invasive test that involves examining the cells in the nipple discharge. It’s particularly helpful in determining whether the discharge is due to a benign or malignant condition.
Fiberoductoscopy is a newer method that allows doctors to directly look into the ducts using a tiny scope. This option is only used for cases presenting with pathologic discharge. It provides an accurate diagnosis of the underlying cause of the discharge.
Minor complications can occur with these tests and procedures, such as local inflammation, but these are usually mild and temporary.
Treatment Options for Mammary Duct Ectasia
The exact cause of Mammary Duct Ectasia (MDE), a breast condition that can cause nipple discharge or discomfort, remains unknown. As a result, treatments are targeted towards relieving symptoms and ruling out more severe diseases.
In mild cases that present only with occasional nipple discharge, doctors will confirm it’s MDE. They will reassure the patient that it’s mostly a harmless condition and monitoring will be all that’s required.
For those with nipple discharge and discomfort, doctors often advise using warm compresses on the central part of the breast. A supportive bra with breast pads helps to absorb any discharge, and it’s crucial to maintain hygiene in the nipple and areola area. These measures help alleviate symptoms and reduce the risk of infection.
Even though MDE is not related to any infection, some of its symptoms can resemble other diseases like mastitis (breast tissue inflammation) or even breast cancer. These could include reddening, swelling, warmth, and pain in the breast area.
Often, oral antibiotics are prescribed, as they help in fighting off common bacteria like Staphylococcus and Streptococcus. Pain medication is also usually given to relieve discomfort. These treatments help most patients to feel better.
If the infection does not improve and progresses to form an abscess (a pocket of pus), different procedures may be required. A small abscess (4 cm or smaller) may be successfully treated by aspirating it, which involves drawing out the fluid with a needle while the patient is on antibiotics. For larger or recurring abscesses, an incision and drainage may be needed. Bacterial cultures can be obtained from drained fluids to tailor appropriate antibiotic therapies.
When symptoms persist or keep recurring, a procedure called microdochectomy may be done. In this surgery, the affected milk duct is removed along with the surrounding inflammation. Doctors might take a swab from the surgical site for bacterial culture to help decide the best antibiotic therapy if needed. However, if the MDE is not accompanied by mastitis, the cultures are quite often free of bacteria. Importantly, MDE does not increase the risk of breast cancer, so routine biopsy may not be required, but it can be considered based on the patient’s individual risk factors.
Smokers or patients with recurring inflammation in and around their milk ducts may need more aggressive treatments including removal of larger parts of mammary duct.
What else can Mammary Duct Ectasia be?
Periductal mastitis (PDM) is a challenging condition to distinguish from mammary duct ectasia (MDE), due to similarities in how they present and how they look on medical images. The absence of a smoking history, more severe inflammation, more frequent flare-ups, and the presence of fistulas are typically seen more with PDM. However, a final diagnosis often needs a tissue examination under a microscope.
Granulomatous lobular mastitis (GLM) is a rare condition where the lobes and ducts of the breast become inflamed, resulting in the formation of a non-decomposing, swollen mass. This mass tends to be tender and is usually found some distance from the nipple. Most of the time, small surgical procedures like lumpectomy or segmental mastectomy are needed, and the tissue is then examined under a microscope to confirm the diagnosis.
Fibrocystic disease often presents with widespread symptoms, cycle-related discomfort, discharge from multiple openings in the nipple, symptoms on both sides, and palpation of cysts not in the nipple zone. An ultrasound is usually enough to diagnose this condition.
Ductal carcinoma in situ (DCIS) or intraductal carcinoma can be hard to identify especially when it’s located near the nipple, as it also involves calcifications, which are common in MDE. Imaging is helpful in such cases, but a needle biopsy is necessary for a final diagnosis.
For intraductal papilloma, it’s important to consider this condition when there’s abnormal bloody nipple discharge. In cases of MDE, the discharge can have different colors. However, in younger patients, a bloody nipple discharge can occur during MDE. Absence of a noticeable thick tube-like structure in the area underneath the nipple tilts the suspicion towards intraductal papilloma. This diagnosis is confirmed by high-resolution ultrasound, examination of the discharge under a microscope, a fiberoductoscopy, and examining tissue removed from a microdochectomy under a microscope.
What to expect with Mammary Duct Ectasia
The outlook for this condition is generally positive as it is a non-cancerous disease and does not increase the risk of developing cancer. The severity of the condition can vary from person to person, with some people getting better on their own without any specific treatment. Others with a more severe form of the disease might require medication or surgery. Despite the disease, life expectancy is not impacted and typically matches that of a similarly aged healthy individual.
Possible Complications When Diagnosed with Mammary Duct Ectasia
The main problems that may occur after the procedure include repeated bouts of inflammation, infections, and abnormal connections between body parts known as fistulas. These complications often necessitate additional procedures and the removal of more duct tissue, leading to scarring around the dark area surrounding the nipple
Common Complications after the procedure:
- Repeated inflammations
- Frequent infections
- Formation of abnormal connections between body parts – Fistulas
- Need for additional procedures
- Extensive removal of duct tissue
- Scarring around the nipple area
Preventing Mammary Duct Ectasia
There currently isn’t a known way to prevent Mammary Duct Ectasia (MDE) because the exact cause is still unknown. But, for those who start showing early signs of the disease with nipple discharge, there are things they can do to help manage the condition. It’s recommended to wear a supportive bra and use breast pads to soak up any discharge. This helps keep the nipple and areola – the circular area around the nipple – clean to avoid any additional infections.
It’s good to know that MDE is not harmful or dangerous. However, quitting smoking can help lessen the risk of getting periductal mastitis, an inflammation in the breast related to smoking, which could worsen the condition and lead to more flare-ups.
It’s always a good idea to get the advice of a general or breast surgeon. They can rule out any serious conditions, like breast cancer, for peace of mind.
