Overview of Fine Needle Aspiration of Breast Masses
Fine needle aspiration (FNA) is a type of health test where a small needle (between sizes 21 to 25) is used to get a sample of tissue or liquid from lumps in the breast, which can be solid or contain fluid. It’s one of several ways to study breast lumps without the need for surgery. Other testing methods include the core needle biopsy (CNB) and Mammotome vacuum-assisted stereotactic biopsy, which are special devices used for breast lumps.
FNA and CNB can be performed with the help of image guidance tools (for example ultrasound) or they can be done without image guidance for lumps that can be felt with the hand. The vacuum-assisted biopsy is done using sonography (a type of medical imaging), mammography (a type of X-ray used for breasts), or MRI (a type of scan that uses strong magnetic fields).
There is a debate among doctors about which is the best method for diagnosing breast lumps because each technique has its own benefits and drawbacks and doctors use them differently in their practices. FNA is often a popular choice because it has many benefits and uses which make it ideal for diagnosing and treating certain breast lumps.
Anatomy and Physiology of Fine Needle Aspiration of Breast Masses
The breasts of a grown woman can be found on the front portion of the chest and are important for producing milk. The breast tissue is situated on a major chest muscle, known as the pectoralis major muscle, and is held in place by various ligaments that connect on both sides of the sternum, which is the long flat bone in the center of the chest. Each breast is made up of 20 sections, or lobes, that spread out evenly below the nipple. Fatty tissue that wraps around each lobe contributes to the shape and size of the breast. Each lobe contains multiple smaller lobules, which produce milk when stimulated by prolactin, which is hormone, and female sex hormones.
The female breast can develop cysts, which are fluid-filled sacs, and solid lumps within the lobes. Most cysts are harmless while most solid lumps are cancerous. Breast cysts generally form at the end of the milk ducts and build up fluid. The majority of breast cysts are small, about 5 to 20 mm in diameter, and they can change size throughout a woman’s menstrual cycle. A woman might have either one or several cysts, which most of the time are painless, but some can cause discomfort or may be noticed when touching or examining the breast.
Breast cysts are greatly affected by hormones and are most common in women who are able to have children. Due to fear of cancer, women often seek medical help. Even though a breast cyst can be felt by touch, sometimes it might be mistaken for a solid mass. So, a common first step in diagnosing cysts is a fine needle aspiration biopsy, which uses a thin needle to extract a sample of the cyst fluid. Some doctors might also order an ultrasound, which is a type of imaging test, before the biopsy to better understand the size, number, and location of the cyst or cysts.
Why do People Need Fine Needle Aspiration of Breast Masses
Fine Needle Aspiration (FNA), a procedure where a thin needle is used to take a sample of tissue, is often recommended for patients who have an unusual mark on a mammogram (an x-ray of the breast) or can feel lumps in their breasts. However, using FNA to diagnose possible breast cancers can be controversial. This is because the procedure only collects a small amount of breast tissue, and there is a high chance the samples may not be sufficient for a diagnosis.
To raise the accuracy of diagnosis, the “triple test” is often carried out. This test incorporates a physical exam, imaging studies (like a mammogram or ultrasound) and cytology (the study of cells) in combination. Additionally, when there are suspect looking nodes (small structures in your body that produce and store cells that fight infection) in the axilla (the area under your shoulder where your arm connects to your body) or armpit, an ultrasound with FNA sampling is advisable.
As a form of treatment, FNA is useful for breast cysts (fluid-filled sacs), especially if they are large, causing symptoms, show abnormal growths, or have odd appearances on imaging. Using FNA can help relieve symptoms and ensure there is no sinister cause behind these abnormalities.
When a Person Should Avoid Fine Needle Aspiration of Breast Masses
There are various circumstances where a Fine-Needle Aspiration (FNA), a type of biopsy that uses a thin, hollow needle to take out samples of cells, should not be performed. These include:
If there’s an existing skin infection, it’s not safe to do an FNA because the needle could potentially spread the infection.
If a patient is on medication that prevents blood from clotting (anticoagulant therapy), an FNA could cause excessive bleeding.
Similarly, an FNA shouldn’t be done on a person who has a bleeding disorder, meaning their blood doesn’t clot properly, because the risk of bleeding is too high.
An FNA always requires the patient’s permission. If the patient doesn’t give their consent, the procedure can’t be performed.
If a patient has a condition known as coagulopathy that affects the blood’s ability to clot, they are also not a suitable candidate for an FNA.
Lastly, if the lesion (a damage or abnormal area of tissue) is positioned deeply and cannot be felt by touching, carrying out an FNA may not be possible.
Equipment used for Fine Needle Aspiration of Breast Masses
This method involves using alcohol wipes, a medical solution called povidone-iodine, sterile gloves, and cloths to maintain cleanliness, a needle of a specific size (21 gauge) with a partially see-through needle hub, and a small syringe that can hold 3 to 5 milliliters. To seal the injection site, we need a plastic bandage and soft gauze. Normally, numbing the area isn’t necessary unless the patient is feeling nervous. However, if the treated area is deep and multiple tries are needed, a local anesthetic called 1% lidocaine may be applied to the skin to reduce discomfort.
Preparing for Fine Needle Aspiration of Breast Masses
Fine needle aspiration is a procedure that’s usually done either in a clinic or an operating room. It’s extremely important that this procedure is done in a perfectly clean, or ‘sterile’, environment to help prevent any infections. This means that everything used for the procedure, even down to the area on the patient’s breast, must be cleaned in a specific way. The doctor performing the procedure also uses completely sterile tools and wears clean gloves, to ensure everything is safe and clean.
How is Fine Needle Aspiration of Breast Masses performed
Fine-Needle Aspiration (FNA) is a type of biopsy procedure, where a thin needle (around 21 to 25 gauge, which is about the size of some insulin needles) is used to extract samples of cells from your body for examination. It’s usually completed through your skin, which is why it’s sometimes called ‘percutaneous.’ Here’s how it works:
First, the skin where the needle will be inserted is cleaned with alcohol, chlorhexidine, or betadine. These are all substances that clean and disinfect the skin to prevent any infection. After cleaning, a local anesthetic (a kind of numbing medication) is applied to reduce any potential discomfort.
Then, the doctor finds the lump or area to be tested either by feeling it (palpation) or with the help of an ultrasound. The ultrasound can project images of the body’s internal structures onto a screen, helping the doctor to accurately guide the needle.
When they’ve located the area, the doctor inserts the needle and pulls the plunger of the syringe back. This creates a suction effect inside the syringe, which helps in collecting a good sample of cells from the targeted area. They usually move the needle in and out (multiple passes) through lumps that feel solid to make sure they get a representative sample.
If the area they’re targeting is more like a liquid-filled sac (cystic), they will draw out all the liquid. The needle may be inserted several times from different angles (this is what we mean by ‘different territories’) to make sure the sample is comprehensive.
Once the samples are collected, they’re sent to the lab for analysis under a microscope – this is where they’ll look for abnormal cells or anything else out of the ordinary.
After the procedure, the doctor checks the area where they inserted the needle to make sure there’s no bleeding or swelling (hematoma). And with that, the procedure is done!
Possible Complications of Fine Needle Aspiration of Breast Masses
Fine-needle aspiration, also known as FNA, may seem like a straightforward process, but it can sometimes lead to complications. These complications can include:
* Bruising or a dark spot on the skin
* Hematoma, which is a swelling of blood leaked into tissues
* Infection
* Pneumothorax, a condition where air fills up the space around the lungs if the needle goes too deep into the chest region
* Pain in the area where the needle was used
Despite these potential complications, it’s important to know that there’s no evidence that FNA causes breast cancer to spread or negatively impacts a person’s likelihood of surviving the disease. Importantly, FNA does not influence the number of false positive results in breast X-rays, also known as mammograms, as long as the doctor is informed beforehand about where the FNA was done.
What Else Should I Know About Fine Needle Aspiration of Breast Masses?
Fine needle aspiration or FNA is a type of biopsy that has several advantages. It is cost-effective, especially if the results are conclusive, meaning there’s no need for more tests. Your doctor can likely do this procedure right in their office. It’s usually less painful and invasive than other methods because it uses a smaller needle. It’s safe for people who are on blood thinners and poses a low risk of complications such as bleeding or forming a hematoma (a collection of clotted blood). It can be used to take samples of tissue from the armpit area (axillary).
However, this procedure does have some downsides. It’s not as accurate at diagnosing as other methods like a core needle biopsy. Between 4% to 13% of the time, it fails to provide enough information or doesn’t yield a diagnosis. It can be tricky to tell the difference between invasive and in-situ carcinoma, a type of cancer that only affects the top layers of cells. This procedure can require a cytopathologist, a doctor who specializes in examining cells and tissues under a microscope, to perform it. If the results aren’t clear, you might need to be re-tested, typically using a CNB or vacuum-assisted method.
Speaking of accuracy, studies on the sensitivity of aspiration cytology (a method to test cells in the body) for detecting cancer have varied. In one test, it is found to be 64% accurate but increases to 91% when three samples are tested. The specificity, however, remains 56% due to inadequate or unsatisfactory preparation of cell samples.
After an FNA, if the sample extracted is not bloody and the cyst (a pocket of fluid) goes away on its own, no further action is needed. Some doctors might want to do an ultrasound just to make sure that the cyst has truly disappeared. This usually happens about 4 to 6 weeks after the biopsy. If the cyst does not go away or if the fluid from it was bloody, you should see a surgeon for a larger, more formal biopsy.
If your doctors think a lump in your breast is due to a galactocele (a milk-filled cyst that can form during breastfeeding or weaning), the goal is typically to manage it carefully without surgery. The FNA might show thick, creamy fluid with a greenish color. Surgery or repeated biopsies might be needed if the galactocele is causing discomfort for the mother. Certain features such as the mass being more wide than tall, having thin walls, heterogeneous contents with fluid clefts, and absence of solid components are consistent with a galactocele.