Biopsy is a diagnostic procedure in which a piece of tissue and/or cells are removed to be examined under a microscope by a pathologist.
Purpose
Biopsies are performed to determine the presence of cancer cells, establish tumor grading, and provide more information for treatment.
Precautions
Most biopsies should not be done on patients with blood clotting problems. If the patient has a low blood platelet count, a platelet transfusion can be given as a temporary relief measure, and a biopsy can then be performed. The physician should be notified of any bleeding problems—as well as any allergies, current medications, or pregnancy—well in advance.
Patients receiving IV sedation for a biopsy procedure will continue to feel drowsy for several hours, and should refrain from cooking, driving, or operating any equipment that requires careful attention. A ride home from the clinic should be arranged in advance.
Description
There are several different types of biopsies, and the decision on which one is most effective depends on where the tumor is located and the general health of the patient. Four common categories of biopsy are fine needle aspiration, core needle biopsy, excisional biopsy, and incisional biopsy.
Fine needle aspiration biopsy
Fine needle aspiration biopsy, also known as suction biopsy or needle aspiration biopsy, involves applying negative pressure through the use of a syringe and hollow, hypodermic needle. This type of biopsy is often used as a diagnostic procedure on neck and thyroid masses. It results in the removal of tissue that is fragmented into cells, as opposed to one sample of undamaged tissue. Fine needle aspiration biopsy is a frequently performed procedure that results in minimum discomfort and is less costly than many other types of biopsy.
Core needle biopsy
Core needle biopsy, also know as wide-core needle biopsy or cutting core biopsy, involves the use of a large-bore needle and is the simplest method of pathologic diagnosis of cancer. It results in minimal disturbance of surrounding tissues and a solid, intact sample. Tumors located in the liver and breast are commonly biopsied with this technique.
Incisional biopsy
This refers to the removal of part of the tumor from the larger tumor mass. An incisional biopsy is employed for tumors located deep within the body and after an initial needle biopsy has failed to supply enough tissue for diagnosis. Biopsies of this type are the preferred technique for diagnosing soft tissue cancers and osteosarcomas.
Excisional biopsy
Also known as surgical biopsy, the excisional biopsy entails the surgical removal of the entire tumor mass and is a diagnostic technique that simultaneously serves as a treatment. For example, a lumpectomy removes the entire primary tumor mass associated with breast cancer. Excisional biopsy is also useful for diagnosing and removing surface tumors of the skin, such as those associated with squamous cell carcinoma, basal cell carcinoma, and malignant melanoma.
Preparation
Many biopsies can be performed in the doctor's office or in the hospital on an outpatient basis. Most do not require much special preparation on the part the patient, but patients should ask their physician for special instructions. Prior to the procedure, most require the use of anesthesia. Prior to and during a biopsy, special imaging techniques may be employed to assist in locating the tumor and guidance of biopsy procedures using a needle. Such imaging techniques include computed tomography scan (CT guided biopsy), fluoroscopy, magnetic resonance imaging (MRI), nuclear medicine scan, and ultrasound (ultrasound guided biopsy). Patients who undergo imaging scans may be injected with or asked to drink a contrast agent (dye) prior to biopsy.
Fine needle aspiration biopsy
Some routine blood work (blood counts, clotting profile) should be completed two weeks prior to biopsy. Patients may be asked not to eat for a specified time before the procedure. Those taking blood thinners (anticoagulants) or aspirin should talk to their physicians about whether they should discontinue using them prior to biopsy.
Core needle biopsy
Women undergoing breast biopsy should not wear talcum powder, deodorant, lotion, or perfume under their arms or on their breasts on the day of the procedure (since these may cause image artifacts or other problems). A comfortable two-piece garment should be worn. Patients may be asked not to eat for a specified time before the procedure. Those taking blood thinners or aspirin should talk to their physicians about whether they should discontinue using them prior to core needle biopsy.
Incisional biopsy
Patients should follow instructions provided by their doctor and give notification of any allergies. Those expecting general anesthesia should not eat or drink for at least 8 hours before an incisional biopsy. Patients should also bathe thoroughly before the procedure and allow time to rest afterward.
Excisional biopsy
Patients may be asked to: sign a consent form allowing the physician to perform this test; refrain from eating or drinking for at least 8 hours prior to surgery; and arrange for a ride home from the hospital (most patients can go home on the same day as the surgery). Those taking insulin, aspirin, non-steroidal anti-inflammatory drugs, or any medicines that affect blood clotting should notify their doctor well before the procedure.
Aftercare
Fine needle aspiration biopsy
After the biopsy, patients should be able to drive home, return to work, or perform any other routine activity. This biopsy does not affect medication schedules.
Core needle biopsy
Most patients can resume normal activities right after the biopsy. If there is excessive redness, pain, or drainage from the puncture site, patients should call their doctor immediately.
Incisional biopsy
After recovering from anesthesia, the patient will be observed for a few hours before returning home. During this time, an analysis may come back from the lab and the doctor may explain the nature of the abnormality. This analysis is the result of only one test and will not be 100% accurate. In about two days, lab testing should be complete. Patients should call their doctor immediately if there is drainage from the wound or a fever develops.
Excisional biopsy
Depending on the invasiveness of the procedure, the patient may receive varied instructions for aftercare. The incision site should be kept clean, dry, and free of lotion, medication, or ointments. The patient may be required to remain in a certain position until sufficient time has passed to warrant the release of the patient from medical care. For example, patients are required to remain on their right side for approximately four hours to allow for healing to occur after a liver punch biopsy. Some patients, however, may be able to return to normal activities on the same day. Those who develop a fever, or notice bleeding, drainage, strong pain, or redness and warmth at the biopsy site should contact their doctor immediately.
Risks
Although most biopsies end with success, there are a certain number of risks to keep in mind. For example, complications can arise if other organs are nicked during a
biopsy using a long needle. As with any procedure, there is a slight risk of allergic reaction to anesthesia. To be well informed, patients should consult with their physician about the risks prior to undergoing the procedure.
Fine needle aspiration biopsy
This biopsy poses no significant risks. Some minor bleeding may occur and some patients report a mild, dull, and throbbing sensation in the area of the biopsy, which usually subsides within 30 to 60 minutes. The risk of infection exists any time the skin is penetrated, but is extremely rare with this procedure. The error rate of diagnosis, however, is substantially higher than that of other biopsy procedures; major surgical resections should not be undertaken solely on the basis of the evidence of aspiration biopsy.
Core needle biopsy
A lumpy scar called a keloid may form in the area of puncture. Infection and bleeding may also occur at or under the biopsy site; however, this risk is uncommon. Core needle biopsy, like fine needle aspiration, only removes samples of a mass and not the entire area of concern. Therefore, it is possible that a more serious diagnosis may be missed by limiting the sampling of an abnormality.
Incisional biopsy
A keloid may form in the incision area. In rare cases, infection and bleeding may occur.
Excisional biopsy
Some patients may experience infection, bleeding, or bruising around the biopsy site. The physician should
be consulted about any risks that may be related to a patient's medical history.
Normal results
The tissue sample obtained from the biopsy needs to be prepared for examination by a pathologist, and results usually are reported to the patient within a few days of the procedure. Normal (negative) results indicate that no malignancy is present.
Abnormal results
Abnormal results indicate that a malignancy or other abnormality is present. In some cases, results are indeterminate and patients are subject to further diagnostic procedures.
Bast, Robert C., et al. Cancer Medicine, 5th ed. Hamilton, ON:B.C. Decker Inc., 2000.
DeVita, Vincent T., Jr. Cancer: Principles and Practice of Oncology. Philadelphia, PA: Lippincott-Raven Publishers, 1997.
OTHER
"An Alternative to Excisional Breast Biopsy: Core Needle Breast Biopsy." Washington Radiology Associates 25 June 2001 <http://www.wrapc.com/corenedl.htm>.
—A substance introduced into the body that allows radiographic visualization of certain tissues. Often used in MRI and CT imaging scans to emphasize the contrast between healthy and cancerous cells.
—Small blood cells that play a role in the blood clotting process.
Tumor grading
—Tumor grade refers to the degree of abnormality of cancer cells compared with normal cells. Establishing a grade allows the physician to determine further courses of treatment.
