Biopsy

views updated May 29 2018

Biopsy

Definition

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 problemsas well as any allergies, current medications, or pregnancywell 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.

See Also Bone marrow aspiration and biopsy; CT-guided biopsy; Liver biopsy; Pleural biopsy; Stereotactic needle biopsy

Resources

BOOKS

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>.

Harvard Health Online 25 June 2001 <http://www.health.harvard.edu>.

National Cancer Institute. 25 June 2001 <http://www.nci.nih.gov>.

Sally C. McFarlane-Parrott

KEY TERMS

Contrast agent

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.

Excision

Surgical removal.

Incision

A surgical cut or gash.

Platelets

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.

Biopsy

views updated May 21 2018

Biopsy

Definition

A biopsy is the removal of a small portion of tissue from the body for microscopic examination.

Description

When a physician diagnoses the nature of an ailment, various examinations provide information that is vital to accurately determining the nature of the problem. Blood and urine samples can be examined to determine the amounts of various compounds. As useful as this information can be, it reveals little about the state of tissues. In diseases such as cancer, knowledge of the affected tissue is crucial for diagnosis and the formulation of treatment strategies.

Examination of tissues can be accomplished without obtaining a sample, using techniques like ultrasound and magnetic resonance imaging (MRI) . However, the information gained may not be detailed enough for a definitive diagnosis. For example, a physician may be interested in the activity of a particular enzyme in the tissue, as a marker of a disease process, or the presence of a toxin. For such determinations, a tissue sample that can be analyzed in the laboratory is needed.

Similarly, for certain diseases and conditions that involve nerve abnormalities, the ability to directly examine nerves can be advantageous in diagnosis and treatment. For instance, direct microscopic examination of a nerve sample can reveal whether or not the protective myelin sheath that surrounds a nerve is intact or is in the process of degrading. Obtaining a nerve via a biopsy is a valuable aid to these examinations.

Muscle biopsies can serve a similar purpose, since maladies that affect the structure and/or functioning of nerves will ultimately affect the muscles into which the nerve passes. The loss of muscle function or strength can be the direct consequence of nerve damage.

Biopsy

A biopsy describes the procedure that is used to obtain a very small piece of the target tissue. For some tissues, like the lining of the cheek, cells can be obtained just by scrapping the tissue surface. Other samples are collected using forceps that are positioned at the end of an optical device called an endoscope. The physician can view the tissue surface (such as the wall of the large intestine) through the endoscope and use the forceps to pluck tissue from the desired region of the surface. In other cases, the tissue sample needs to be collected as a "plug," using a large hypodermic needle. Examples of the latter include liver or kidney biopsy samples. Samples of muscles and nerves can also be obtained by cutting out a small piece of the target once an incision has been made.

When a biopsy is obtained using a needle, the retrieval of a sample relies on the design of the needle and the energy of its insertion into the tissue. The needle used is a hollow tube with a sharp point capable of puncturing tissue. As the needle is driven deeper into a tissue following puncture, tissue will accumulate in the hollow tube. When the needle is withdrawn from the tissue, the plug of tissue remains in the needle tube and can be retrieved for analysis.

Many biopsy samples are examined using a light microscope to look for abnormalities in the tissues cells. This examination can involve the staining of the sample to specifically detect target molecules. As well, samples can be used for various biochemical tests, and even to test for the presence and activity of particular genes.

A biopsy can remove the entire target region (excisional biopsy) or can remove just a small portion of the target region (incisional biopsy). The latter can be done in three different ways, depending on the sample. A shave biopsy slices off surface tissue. Samples collected by piercing the tissue with a needle represent a punch biopsy. Finally, in fine needle aspiration, a needle is inserted and tissue is subsequently withdrawn into the needle using a syringe.

Muscle biopsy

A muscle biopsy can represent the punch type, in which a plug of tissue is obtained using an inserted needle. Or, in an open biopsy procedure, a small incision is made and a piece of tissue is removed. This biopsy is done for a variety of reasons: to distinguish between nerve and muscle disorders, to identify specific muscular disorders such as muscular dystrophy , to probe muscle metabolic activities, and to detect muscle infections such as trichinosis and toxoplasmosis. Biopsy of a muscle necessarily involves nerves, as muscle is highly infused by nerves. The small amount of muscle that is extracted during a muscle biopsy does not damage nerves to such an extent that muscle function is affected.

Brain biopsy

A brain biopsy is performed following the drilling of a hole in the skull, through which the biopsy needle is subsequently introduced. An MRI or computed tomography (CT ) scan is performed prior to the procedure in order to identify the area where the biopsy will be performed. As of the mid-1990s, the patient's head is no longer immobilized during the procedure by a frame device. Instead, the precise location is located by a computer-guided system that is designed to avoid damage to other regions of the brain. In contrast to a skin biopsy, for example, where the sample scraping may affect few nerves, a brain biopsy is a delicate and potentially problematic procedure. Rarely, nerve damage may result, and the puncture site may form scar tissue, causing seizures .

Nerve biopsy

Nerves such as the sural nerve in the ankle and the superficial radial nerve in the wrist are most often used for a nerve biopsy. A nerve biopsy is performed to detect nerve-damaging conditions, including leprosy, necrotizing vasculitis (an inflammation of the blood vessels), other nerve inflammation, and damage or loss of the nerve's protective myelin sheath (demyelination). A nerve biopsy can also be done to try to identify nerve abnormalities that are generically called neuropathies, or to confirm a specific diagnosis relating to a nerve. An example is the progressive wasting away of muscle tissue in the feet and legs that is known as Charcot-Marie-Tooth disease.

When a nerve biopsy is performed, local anesthetic is used. Then a small incision is made and a small piece of the target nerve is removed. Usually, a biopsy of the adjacent muscle is done at the same time. The biopsy procedure carries minimal risks, including allergic reaction to the anesthetic, infection, and permanent numbness. A small degree of persistent numbness is to be expected, however, because a portion of nerve has been removed. As a nerve biopsy is generally performed in the ankle or wrist, the numbness is typically not debilitating and is seldom recognized during normal activities.

Biopsy sample processing and examination

Biopsy specimens are often sliced into thin slices, stained, mounted on a glass slide, and examined using a light microscope. Newer sample preparation techniques involve the rapid freezing of the sample and slicing of the still-frozen material. The latter technique has the advantage of avoiding the removal of water, which can alter the structure of the tissue cells. Microscopic examination focuses on the general appearance of the cells, including their structure, presence of abnormalities, and specific molecules that have been revealed by the use of specialized stains or antibodies. This interpretation can be subjective, and relies on the expertise of the experienced examiner.

Resources

BOOKS

Zaret, B. L. The Yale University School of Medicine Patient's Guide to Medical Tests. New Haven: Yale University School of Medicine and G.S. Sharpe Communications Inc., 1997.

OTHER

National Library of Medicine. "Muscle Biopsy." Medline Plus. May 5, 2004 (May 27, 2004). <http://www.nlm.nih.gov/medlineplus/ency/article/003924.htm>.

National Library of Medicine. "Nerve Biopsy." Medline Plus. May 5, 2004 (May 27, 2004). <http://www.nlm.nih.gov/medlineplus/ency/article/003928.htm>.

"What Is a Biopsy?" Netdoctor.co.uk. May 6, 2004 (May 27, 2004). <http://www.netdoctor.co.uk/health_advice/examinations/biopsy.htm>.

ORGANIZATIONS

American Academy of Neurology. 1080 Montreal Avenue, Saint Paul, MN 55116. (651) 695-2717 or (800) 879-1960; Fax: (651) 695-2791. [email protected]. <http://www.aan.com>.

Brian Douglas Hoyle, PhD

biopsy

views updated May 17 2018

biopsy A piece of tissue taken from a patient during life to establish a precise diagnosis so that the most appropriate treatment can be initiated. Usually a thin section of the specimen on a glass slide is examined by a pathologist under a microscope, but if the specimen is small and soft it may be more appropriate to make a smear on the slide. On occasion the biopsy may require to be examined biochemically. Biopsies may also be taken, for example, from chorionic villi (the projections of fetal tissue around the early embryo after it is embedded in the womb) for chromosomal analysis when a hereditary disorder is suspected.

The technique of biopsy is vital in all branches of medicine. Various methods are used. The simplest is a scraping from an accessible site such as the skin, or from a mucous membrane, such as in the mouth or the cervix of the womb. One of the commonest is a needle biopsy when a small sample is sucked out into some type of syringe through a needle of a calibre appropriate to the consistency of the tissue. This method is applicable to obtaining tissue from the breast, kidney, liver, brain, or heart.

In other situations a lesion is biopsied by a surgeon either at an operation undertaken just for that purpose, or in the course of an exploratory procedure. Often only part of the lesion being investigated is taken at operation — an incisional biopsy, but if the lesion is small, such as an ulcer, a pigmented spot on the skin, or a lymph node it may be removed in its entirety: an excision biopsy. Procedures of this type involve the use of a scalpel. Other instruments may be appropriate: a curette is used to take scrapings from the inner lining of the womb (the endometrium); small biopsies may be obtained by endoscopy — from the lungs during bronchoscopy, or from the lining of the stomach or colon. Occasionally specially designed instruments are used, in the form of ‘punches’ or ‘brushes’.

One of the commonest reasons for undertaking a biopsy is to establish whether a tumour is malignant or benign. A common example of this is the investigation of a lump in a woman's breast. In such circumstances the pathologist often undertakes an immediate microscopical examination while the patient is still in the operating theatre, the surgeon waiting for the result before deciding how extensive an operation is required. This is also a common procedure during operations for tumours of the brain, or for cancers in other sites when lymph nodes need to be examined to establish whether or not they have been invaded by malignant cells.

Apart from the assessment of malignancy, biopsies are taken to examine organs such as the liver or kidneys for evidence of intrinsic disease, or to look for any signs of rejection of a transplanted organ such as a kidney or a heart.

Needle biopsies of skeletal muscles are often taken because of the problems frequently encountered in distinguishing clinically among conditions caused by disease in the muscle itself (myositis, muscular dystrophy) and those secondary to an abnormality in its nerve supply.

Healthy individuals are not always exempt — for example they may be recruited as volunteers for muscle biopsy. Enthusiasm for competitive sport and interest in the health-promoting effects of exercise in recent decades have provided an increasing incentive (and funds) for improving knowledge about skeletal muscle and the effects upon it of various training and dietary regimes. Needle biopsy of muscles has become a standard component of investigations in major research laboratories for sport and exercise science.

J. Hume Adams


See also cancer; muscle; neoplasm; transplantation.

biopsy

views updated May 21 2018

bi·op·sy / ˈbīˌäpsē/ • n. (pl. -sies) an examination of tissue removed from a living body to discover the presence, cause, or extent of a disease.

biopsy

views updated May 17 2018

biopsy Removal of a small piece of tissue from a patient for examination for evidence of disease. An example is the cervical biopsy (‘smear test’), performed in order to screen for pre-cancerous changes that can lead to cervical cancer.

biopsy

views updated May 18 2018

biopsy The removal of a small section of tissue from a potentially diseased organ or tissue in a living organism. The biopsied tissue is usually analysed by microscopic techniques in order to identify the nature of the disease.

biopsy

views updated May 11 2018

biopsy (by-op-si) n. the removal of a small piece of living tissue from an organ or part of the body for microscopic examination.