What is Breast Cyst?
Breast cysts are very common in women and are often the reason for being referred to a breast clinic. They are typically the main cause of breast lumps or discomfort. They are a part of a larger non-cancerous condition called fibrocystic breast disease. This condition involves changes in the breast tissue that can involve the development of fibrous tissue and cysts. A breast cyst is a fluid-filled sac located within the breast tissue, which can range in size from very small to large and can be present as a single cyst or several. Some cysts do not cause any symptoms and are only found by chance, while others may cause lumps, pain, or discharge from the nipple. Research shows that between 70% and 90% of women might experience fibrocystic breast disease at some point in their lives.
These fibrocystic changes are categorized depending on their features. These categories include nonproliferative, proliferative without atypical cells or proliferative with atypical cells. While the lumps and pain can be alarming for patients, it’s very rare for breast cancer to cause pain. In addition, having fibrocystic breast disease alone is not specifically a risk factor for developing breast cancer. But, there is an increase in the risk of breast cancer when fibrocystic changes include atypical cells. Also, other cancerous cysts can develop, which can resemble common benign breast cysts. The link between fibrocystic changes and breast cancer is complicated and a topic of ongoing debate. It’s crucial to properly diagnose, treat, and manage breast cysts due to these complexities.
What Causes Breast Cyst?
The exact cause of breast cysts is not known. However, it’s commonly believed that most breast cysts are linked to a condition called Aberration of Normal Development and Involution (ANDI). ANDI suggests that many benign, or non-cancerous, breast diseases occur due to minor irregularities in the standard physiological processes of breast growth and natural reduction in size, which normally follow a regular growth cycle.
Risk Factors and Frequency for Breast Cyst
Fibrocystic breast disease is a common condition among women, with over 70% experiencing fibrocystic changes during their lives. Around 20% of those affected will display symptoms, and between 10% to 30% may develop a condition called sclerosing adenosis. In fact, it is estimated that about 7% of all women in the United States will find a noticeable cyst in their breast at some point.
- Over 70% of women develop fibrocystic changes during their life.
- 20% of these women show symptoms.
- 10%-30% of the affected women may develop sclerosing adenosis.
- It’s estimated that about 7% of all women in the United States will develop a palpable breast cyst at some point.
- Breast cysts usually occur in women aged 30 to 50.
- Cyst development rises throughout these years and then drastically decreases afterwards.
- Since cyst development is related to hormone levels, most benign cysts disappear, and new cysts stop forming around a year post menopause.
Signs and Symptoms of Breast Cyst
Fibrocystic breast changes often cause breast tenderness and pain right before menstruation, known as cyclic mastalgia. However, most women discover they have fibrocystic changes when they find a lump in their breast, not because of pain. Properly diagnosing these breast changes involves three steps: a clinical evaluation, imaging tests, and a tissue sample test, either by fine-needle aspiration or core needle biopsy.
In the first step, the clinical evaluation, doctors will gather detailed information about the problem, such as a description of the pain and how it relates to the woman’s menstrual cycle, any recent injuries to the area, changes to the nipple and skin, and any nipple discharge. The doctor will also need to know about the woman’s medical and surgical history, family history, current medications and medication allergies. They will need specific details like when the woman first started menstruating, if she has gone through menopause, and if she or her family has a history of breast cancer. After gathering this information, the doctor will do a full physical examination, checking both breasts and looking for any swollen lymph nodes in the armpits, neck, and chest.
- Increase in breast tenderness and/or pain before menstruation
- Palpable breast lump
- Diagnosis methods include clinical evaluation, imaging, and tissue sample testing
- Clinical evaluation encompasses detailed history of the problem, personal medical history, current medications, family history, and physical examination
Testing for Breast Cyst
The second part of investigating suspicious breast changes typically involves imaging and tissue sampling for testing.
With ultrasound, there are two main types of growths that can be seen. Simple cysts appear as round shapes, with clear borders, and little to no internal echoes. These are usually harmless and do not require intervention unless they are causing discomfort. Complex cysts, on the other hand, look different on the ultrasound. They have varied echoes within them, visible debris that moves when the patient changes posture, and may have thicker walls, internal lumps, or solid parts. They can fall into four categories based on how they look, and can sometimes imply a higher risk of cancer.
Mammograms or breast X-rays don’t distinguish between fluid-filled cysts or solid lumps as well as ultrasound does. However, they are helpful for women over 35 years who typically have less dense breast tissue. For younger women, who tend to have denser breast tissue, ultrasound is often more useful. Mammograms can still provide useful insight by detecting certain abnormal features, like tiny calcium deposits.
Magnetic resonance imaging (MRI) can also be used, but it isn’t as common as ultrasound or mammography due to its high cost and limited availability.
An important classification system has been created by the American College of Radiology, this includes six categories each correlating with a different likelihood of cancer.
The final step of the triple assessment involves taking a small sample of tissue and testing it in a laboratory. This can be done using a fine needle to remove fluid or a more substantial core needle for sampling solid lumps. The appearance of the removed fluid can provide useful information about the nature of the growth. For instance, clear or pale yellow fluid is typical of simple cysts whereas green or thick fluid can indicate specific conditions such as a milk-filled cyst (galactocele). Any fluid that is bloodstained or looks like pus should be sent for further testing.
If a fluid-filled cyst disappears after being drained with a needle, it is generally considered treated. However, if the cyst comes back, or if the ultrasound or mammogram suggest some solid parts or abnormal features, a core needle biopsy can be done to retrieve a larger tissue sample. If a cyst keeps returning even after core needle biopsies, or if a good sample was not collected, surgical removal of a sample (excisional biopsy) may be considered.
Treatment Options for Breast Cyst
When a simple cyst is drained, it usually disappears and no further treatment is necessary. Doctors may have different ways of checking to see if the cyst is gone. Some might ask you to come back 4-6 weeks after the procedure for another scan. If the cyst fills up again quickly, it could mean it’s a cancerous cyst. However, because cancer is very rare in simple cysts, some experts believe that this check-up isn’t always necessary unless you have new symptoms or feel a lump again.
Complex cysts are monitored more closely. If the detection of the cyst types and structures looks non-cancerous after it’s drained or biopsied, you might need to have another scan every six months to a year over a two-year period. If there are no changes after two years, you can stop getting scans. But if anything looks worrying, you might have another biopsy or surgery to remove it.
Most breast cysts are benign, or non-cancerous, and don’t need cancer treatment. If a cyst is found to be cancerous, then it’s treated like breast cancer. This can involve a mix of surgery to remove the cyst and extra treatment. The extra treatment could involve hormone therapy, chemotherapy, radiotherapy, immunotherapy, or biological agents.
What else can Breast Cyst be?
When doctors are diagnosing breast cysts, they have to consider a number of different possible conditions. Some of these conditions are less serious, while others could mean cancer. For example, larger papillomas, which are usually harmless, can sometimes look like complex cysts. Similarly, an infection in the breast can present like a cyst, but this is a completely different condition. Other confusing factors could include phyllodes tumors or radial scars, which can sometimes have components that look like cysts.
It’s incredibly rare for a cyst to be cancerous. In fact, one study found that out of 3000 cysts studied, only three were cancerous. One type of breast cancer, called ACC (adenoid cystic carcinoma), actually originates from a type of salivary gland tumor, but can occur in the breast. Even though ACC is a form of cancer, it doesn’t often spread to other parts of the body, making it less dangerous than other types. In fact, when it is low-grade, patients with ACC have excellent survival rates.
What to expect with Breast Cyst
The outlook for breast cysts can change based on the cause of the cyst. If the cyst is a simple breast cyst that doesn’t contain any solid parts and goes away after being drained, it’s completely harmless. However, if the cyst has solid parts or if it comes back after being drained, there could be an underlying cancer.
Although very rare, accounting for only 0.1% to 1% of all breast cancers, intracystic carcinoma (a type of cancer that occurs within a cyst) is a possibility that should be considered when evaluating a breast cyst.
Possible Complications When Diagnosed with Breast Cyst
When we talk about complications from breast cysts, they usually happen after an attempted removal of the cyst fluid. Post-procedure swelling or a large bruise can occur, as well as the potential for germs to enter the site causing a pocket of infection to form. The existence of a breast cyst and changes to the texture of the nearby tissue it causes, along with the procedure to remove fluid from it, as well as any resultant swelling or bruising, can all negatively affect the accuracy of a mammogram. This can lead to misleading positive results. Therefore, it’s often advised to delay mammograms by two weeks from when the procedure was done or until any swelling has gone down. It’s also crucial to give the radiologist clear information about the patient’s medical history.
If a procedure to remove fluid from the cyst is not carried out in a sterile environment, there’s a chance that harmful microbes can be introduced into the breast, which can cause inflammation of the breast tissue or a breast abscess. Additionally, procedures removing fluid or taking a tissue sample from the cyst could cause potentially cancerous cells to spread to healthy breast tissue nearby, if there’s a hidden cancer present.
Preventing Breast Cyst
If you’re experiencing any symptoms related to breast health, it’s critical to seek medical attention promptly. While most of these symptoms might be due to harmless fibrocystic changes in breast tissue, it’s still crucial to conduct thorough examinations to make sure they’re not cancerous. Importantly, most cyclic breast pain – pain that comes and goes with your menstrual cycle – isn’t associated with a detectable lump in the breast and can, therefore, be challenging to treat properly.
For a comprehensive evaluation of any breast lump, women should undergo a three-part assessment. This process includes a recount of symptoms and physical examination, imaging tests such as ultrasound or mammography, and, finally, a tissue or cell analysis. These steps are vital in diagnosing and designing an effective treatment plan.
