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Biopsy of Breast

What is a biopsy of the breast?

A breast biopsy is a test in which a small piece of tissue or sometimes fluid is taken from the area of concern. The cells that are taken out are looked at under a microscope and put through more tests to see if they have breast cancer. The only way to find out for sure if the suspicious area is cancerous is to do a biopsy.

The good news is that 80% of the time, a breast biopsy does not show that a woman has breast cancer.

Biopsies come in three different forms:

  • Fine-needle aspiration

  • Needle core biopsy

  • Biopsy surgery

The latter two are the most commonly used on the breast.

There are several factors that help a doctor decide which type of biopsy to recommend. These include the appearance, size, and location of the suspicious area on the breast. Before discussing biopsy results, let’s first distinguish between the three types of biopsies.

What is fine-needle aspiration?

In most cases, a fine needle aspiration is chosen when the lump is likely to be filled with fluid. If the lump is easily accessible or if the doctor suspects that it may be a fluid-filled cystic lump, the doctor may choose to conduct a fine-needle aspiration (FNA) (FNA). During this procedure, the lump should collapse once the fluid inside has been drawn and discarded. Sometimes, an ultrasound is used to help your doctor guide the needle to the exact site, whereby sound waves create a picture of the inside of the breast.

If the lump persists, the surgeon or radiologist, a doctor who specializes in medical imaging such as x-rays and mammograms, will perform a fine needle aspiration biopsy (FNABx), a similar procedure using the needle to obtain cells from the lump for examination.

What is a core-needle biopsy?

Core needle biopsy is the procedure to remove a small amount of suspicious tissue from the breast with a larger “core” (meaning “hollow”) needle. It is usually performed while the patient is under local anesthesia, meaning the breast is numbed. During the procedure, the doctor may insert a very small marker inside the breast to mark the location of the biopsy. If surgery is later required, the marker makes it easier for the surgeon to locate the abnormal area. Even if you don't need any more treatment, like surgery, the marker lets a breast imaging radiologist see where the biopsy was done on future mammograms.

When doing a core-needle biopsy, the radiologist or surgeon may use special imaging equipment to help guide the needle to the right place. Like with fine-needle aspiration, ultrasound may be used.

During an ultrasound-guided core needle biopsy, the patient lies down while the doctor holds the ultrasound against the breast to guide the needle. During a stereotactic-guided core-needle biopsy, on the other hand, the doctor guides the needle with the help of an x-ray machine and a computer. Most of the time, the patient lies on his or her stomach on a special table with a hole for the breast. The breast is then compressed, just like in a mammogram.

Sometimes, no imaging equipment is used, but this is usually only the case when the lump can be felt through the skin. A freehand core-needle biopsy is this kind of procedure.

A core-needle biopsy is less likely to cause side effects than a surgical biopsy.

What can I expect from a surgery to take a sample?

(Also called "wide local excision," "wide local surgical biopsy," "open biopsy," or "lumpectomy.")

A surgical biopsy is done while the patient is under local anesthesia, just like a core-needle biopsy. Most of the time, this test is done in a hospital, where the patient is given an IV and drugs to make them sleepy.

The surgeon makes a one- to two-inch cut in the breast and then removes all or part of the abnormal lump as well as a small amount of normal-looking tissue, called the "margin." If the lump is hard to feel but can be seen on a mammogram or ultrasound, a radiologist may put a thin wire into the area to mark it before the surgeon does the biopsy. Again, at the end of the procedure, a marker is usually put inside the body at the site of the biopsy.

What can we learn from the results of the biopsy?

Once the biopsy is done, the tissue or fluid samples are looked at under a microscope by a doctor with special training called a pathologist. The pathologist is looking for abnormal or cancerous cells. The patient's doctor gets the pathology report, which can take up to two weeks to finish. It tells you if the suspicious spot is cancerous and gives you a full picture of what's going on. Waiting for results can be hard on the patient, but it's well worth it to be able to make an informed choice about your treatment. Your doctor will talk to you about the report and, if necessary, talk about the possible treatments.

If there are no cancer cells, the report will say that the lump's cells are benign, which means they are not cancerous. But the doctor or nurse may still suggest that you get some kind of follow-up care or treatment.

If there are cancer cells, the report will give more information to help decide what to do next.

The report for a core-needle biopsy sample will say what kind of tumor it is and how fast it is growing. If cancer is found, the pathologist will also look for estrogen or progesterone receptors on the cells in the lab.

In the case of a surgical biopsy, the results show information about the tumor's type, grade, and receptor status, as well as the distance between the removed tumor and the normal tissue around it. As we said before, the margin shows whether or not there are any cancer cells at the site.

If the margin is positive, it means that there are cancer cells at the edge of the tumor. When the margins are positive, the cancer has spread to other parts of the body.

A margin that is negative or clear means that there are no tumor cells at the edge. This means that the cancer is only in the area around the tumor.

A close margin means that there is less than about 3 mm of space between the cancerous tissue and the normal tissue around it (0.118 inch).

If a biopsy shows that you have cancer, the pathology report will help you and your doctor decide what to do next. You will probably be sent to a breast cancer specialist, and you may need more scans, lab tests, or surgery. The pathology report and the results of the other tests are used by your medical team to figure out the stage of your cancer and come up with the best treatment plan for you.

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