Breast Biopsy

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Breast Biopsy

Definition
Purpose
Demographics
Description
Diagnosis/Preparation
Aftercare
Risks
Normal results
Morbidity and mortality rates
Alternatives

Definition

A breast biopsy is the removal of breast tissue for examination by a pathologist. This can be accomplished surgically or by extracting tissue through a needle.

Purpose

Breast biopsies are done to diagnose breast abnormalities. A biopsy is recommended when a significant abnormality is found by physical examination or an imaging test. Examples of an abnormality can include a breast lump felt during breast self-examination or tissue changes noticed from a mammogram.

Before a biopsy is performed, other simpler, less invasive tests may be done to rule out cancer. For example, a lump may be revealed simply as a fluid-filled cyst when examined by ultrasound imaging. If less invasive tests are not conclusive, the presence of a malignant (cancerous) or benign (noncancerous) breast condition can be definitively determined by a biopsy.

Demographics

The American Cancer Society estimated that in 2007, 78,480 new cases of invasive breast cancer and 62,030 new cases of breast carcinoma in situ (CIS) were diagnosed in the United States. CIS is the earliest, noninvasive form of breast cancer. Approximately one of every eight women will develop breast cancer at some point in her life. Since 1990, breast cancer rates have decreased among women under age 50; however, breast cancer still causes the death of one of every 35 women.

In 2007, the incidence of breast cancer was highest among Caucasian women, but African American women had more aggressive tumors and were more likely to die from the disease. Hispanic, Native American, and Asian women have lower breast cancer and breast cancer death rates than Caucasians or African Americans.

Description

In a biopsy, cells are removed from the breast and examined under the microscope to determine if they are malignant or benign. The type of biopsy recommended depends on whether the abnormality is large enough to be felt, how well it can be seen on mammogram or ultrasound, and how suspicious it feels or appears. Specialized equipment is needed for different types of biopsy, and its availability may vary.

Surgical biopsy

There are two types of surgical breast biopsy: excisional and incisional. An excisional biopsy is a surgical procedure that removes the entire area of concern and some surrounding tissue. It is usually done as an outpatient procedure in a hospital or freestanding surgery center. The patient may be awake, but is usually given medication to make her drowsy. The area to be operated on is numbed with a local anesthetic. Infrequently, general anesthesia is used. An excisional biopsy usually takes under one hour to perform. Nevertheless, the total amount of time spent at the facility depends on the type of anesthesia used, whether a needle localization was done, and the extent of the surgery.

If a mass is very large, an incisional biopsy may be performed. In this case, only a portion of the area of concern is removed and sent for analysis. The procedure is the same as an excisional biopsy in other respects.

Needle biopsies

A needle biopsy removes a sample of fluid and cells from suspicious area for examination. There are two main types or needle biopsies: aspiration biopsy, using a fine-gauge needle, and large-core needle biopsy. Either of these may be called a percutaneous needle biopsy. Percutaneous refers to a procedure done through the skin.

A fine-needle aspiration biopsy (FNAB) uses a very thin needle to withdraw (aspirate) fluid and cells that are then examined under the microscope for abnormalities. A FNAB can be done in a doctor’s office, clinic, or hospital. Local anesthetic may be used, but is sometimes not needed as its administration may be more painful than the insertion of the very thin biopsy needle. Sometimes, the area to place the needle may be located by touch without using specialized equipment. However, ultrasound guidance enables the physician to feel and see the lesion at the same

KEY TERMS

Core needle biopsy (CNB)— A procedure using a larger diameter needle to remove a core of tissue from the breast.

Ductogram— A test used for imaging the breast ducts and diagnosing the cause of abnormal nipple discharges.

Fine-needle aspiration biopsy (FNAB)— A procedure using a thin needle to remove fluid and cells from a lump in the breast.

Mammogram— A set of x rays taken of the front and side of the breast used to help diagnose various breast abnormalities.

time. This helps ensure that the specimen is taken from the area of concern. The patient lies on her back or side. After the area is numbed, sterile gel is applied. The physician places a transducer, an instrument about the size of an electric shaver, over the skin. This produces an image from the reflection of sound waves. A special needle, usually in a spring-loaded device, is used to obtain the tissue. The actual withdrawal of fluid and cells can be visualized as it occurs.

A core needle biopsy (CNB) uses a larger diameter needle to remove small pieces of tissue. These are usually about the size of a grain of rice, although the needle diameter may vary based on the size and location of the suspicious mass. CNBs can be done in a clinic or hospital. Local anesthetic is routinely used. Ultrasound or x ray is used to guide the placement of the needle in a core needle biopsy. When larger cores are removed, a vacuum pump may be used to help withdraw the tissue.

If the suspicious area is seen best with x ray, a stereotactic device is used to guide the biopsy. X rays are taken from several angles. The information is fed into a computer that analyzes the data and guides the needle to the correct place. The patient may be sitting up, or she may be lying on her stomach, with her breast positioned through an opening in the table. The breast is held firmly but comfortably between a plastic paddle and a metal plate, similar to those used for mammograms. X rays may be taken before, during, and after the tissue is drawn into the needle to confirm that the correct spot is biopsied. This procedure is called a stereotactic core biopsy, or a mammotomy.

A pathologist examines the sample tissue for malignant cells, indicating the presence of cancer. If a fine-needle aspiration biopsy is performed, the pathologist looks at individual cells under the microscope to see if they appear abnormal. CNBs and surgical biopsy often provide more information than FNABs and are able to give more information on the type of cancer, whether it has invaded surrounding tissue, and how likely it is to spread quickly. The biopsy can also reveal some conditions that are not malignant but indicate high risk for future development of breast cancer. If these are identified, more frequent breast monitoring is recommended.

Diagnosis/Preparation

Sometimes an abnormality can be felt during a breast self-examination or an examination by a healthcare professional. If an abnormality is not felt, there are other signs that indicate the need for medical attention. These include:

  • severe breast pain
  • changes in the size of a breast or nipple
  • changes in the shape of both breast and nipple
  • pitting, dimpling, or redness of the breast skin
  • nipple redness, irritation, or inversion
  • changes in the pattern of veins visible on the surface of the breast
  • some types of nipple discharge

If the abnormality cannot be located easily, a wire localization may be done before the actual biopsy. After local anesthetic is administered, a fine wire is placed in the area of concern. Either x ray or ultrasound guidance is used to place the wire, and then the biopsy needle can follow the wire to the area of concern. The patient is awake and usually sitting up during this procedure.

A surgical breast biopsy may require that patient have nothing to eat or drink for some time before the operation. This will typically be from midnight the night before the procedure, if general anesthesia is planned. No food restrictions are necessary for needle biopsies, although it is advisable to eat lightly before the procedure. This is especially important if the patient will be lying on her stomach for a stereotactic biopsy.

Aftercare

After a surgical biopsy, the incision is closed with sutures and covered with a bandage. The bandage is usually removed within two days. Sutures are removed about one week later. Depending on the extent of the operation, normal activities can be resumed in one to three days. Vigorous exercise may be limited for one to three weeks.

WHO PERFORMS THE PROCEDURE AND WHERE IS IT PERFORMED?

A surgeon, or a radiologist, which is a medical doctor who specializes in the use of imaging techniques for diagnosis or treatment, usually performs breast biopsy. A pathologist, who is a medical doctor who has completed specialized training in the diagnosis of diseases from microscopic analysis of cells and tissues, analyzes the extracted tissue samples. Surgical biopsies are generally performed at a hospital or surgery center. Because needle biopsies are less invasive, they may be performed at a doctor’s office, clinic, or hospital.

The skin opening for a needle biopsy is minimal. It may be closed with thin, clear tape or covered with a small bandage. The patient can return to her usual routine immediately after the biopsy. Strenuous activity or heavy lifting should be avoided for 24 hours. Any bandages can be removed one or two days after the biopsy.

Risks

Infection is always a possibility when the skin is broken, although this rarely occurs in breast biopsies. Redness, swelling, or severe pain at the biopsy site indicates a possible infection and a reason for concern. Another possible consequence of a breast biopsy is a hematoma, which is a collection of blood at the biopsy site. The body usually resorbs this blood naturally without treatment. If the hematoma is very large and uncomfortable, it may need to be drained. A surgical breast biopsy may produce a visible scar on the breast. Scarring may make future mammograms harder to interpret accurately.

A false negative pathology report is another risk. In a false negative report, no cancer is found when cancer is actually present. The incidence of false negative biopsy findings varies with the biopsy technique. In general, fine-needle aspiration biopsies have the highest rate of false negative results. Different facilities also have varying rates of false negative readings, depending somewhat on the experience of their pathologist.

Normal results

A normal pathology report indicates no malignancy is present. The tissue sample may be classified

QUESTIONS TO ASK THE DOCTOR

  • Why is a biopsy recommended?
  • What type of biopsy will I have?
  • How long will the procedure take?
  • When will I find out the results?
  • What will happen if the results are positive for cancer?

as a benign breast condition. Many women develop nonmalignant tumors of the breast (fibroadenoma) or harmless fluid-filled cysts. Some noncancerous conditions are more likely to develop into cancer. Women with these benign conditions should have more frequent breast health check-ups. Some studies have found that about 80% of all breast biopsies result in a negative (noncancer) pathology report.

Morbidity and mortality rates

The reported rate of complications for image-guided biopsies is approximately 2%. Excessive bleeding occurs after approximately 0.5% of fine needle biopsies, 3% of small needle biopsies, and 5–10% of large needle biopsies. Infection occurs in approximately 1% of biopsy sites. Organ damage such as a collapsed lung (pneumothorax) occurs in approximately 0.5% of biopsies. The rate of complications varies considerably among individual physicians and facilities.

Alternatives

While a biopsy is the only way to determine definitively if a breast abnormality is cancerous, other less invasive procedures may be done to try to rule out cancer so that a biopsy is not necessary. These include mammography, ultrasound imaging, and ductography (used for imaging the breast ducts and diagnosing the cause of abnormal nipple discharges).

Resources

ORGANIZATIONS

American Cancer Society. 1599 Clifton Rd., NE, Atlanta, GA 30329-4251. (800) 227-2345. http://www.cancer.org (accessed March 8, 2008).

National Cancer Institute. NCI Public Inquiries Office, 6116 Executive Boulevard Room 3036A, Bethesda, MD 20892-8322. (800) 422-6237. TTY: (800) 332-8615 http://www.nci.nih.gov (accessed march 8, 2008).

OTHER

Cardella, John F., et al. “Breast Biopsy.” MedicineNet. April 11, 2002 [cited January 2, 2008]. http://www.medicinenet.com/breastbiopsy/article.htm.

_How is Breast Cancer Diagnosed?” American Cancer Society. September 13, 2007 [cited January 2, 2008]. http://www.cancer.org/docroot/CRI/content/CRI_2_4_3X_How_is_breast_cancer_diagnosed_5.asp.

“Lifetime Probability of Breast Cancer in American Women.” National Cancer Institute. October 5, 2006 [cited January 2, 2008]. http://cis.nci.nih.gov/fact/5_6.htm.

Ellen S. Weber, MSN

Stephanie Dionne Sherk

Tish Davidson, AM