biopsy

biopsy, examination of cells or tissues removed from a living organism. Excised material may be studied in order to diagnose disease or to confirm findings of normality. Preparatory techniques depend on the nature of the tissue and the kind of study intended. Incisions may be made and total or partial lesions removed in the form of wedges or cylindrical pieces, or scrapings of the surface membranes of internal organs may be collected. Needlelike instruments may be used to pierce the tissues and remove soft inner material. Once the tissue specimen has been obtained it is fixed, i.e., membrane proteins and enzymes are stabilized and chemical and histologic analyses are carried out by pathologists. Tumors are routinely biopsied in order to determine whether they are malignant. Fine needle aspiration is a technique more readily used for certain tumors or lesions because it is less expensive and damaging than traditional surgical biopsy.

Procedure in which cells or tissues are removed from a patient and examined. The sample may be obtained from any organ, by any of several methods, including suction through a needle, swabbing, scraping, endoscopy, and cutting out the entire structure or part of it to be tested. Biopsy is a standard step in distinguishing malignant from benign tumours and can provide other information for diagnosis, particularly concerning such organs as the liver or pancreas. Slides of the tissue are prepared and examined by microscope.

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A biopsy (in Greek: βίος life and όψη look/appearance) is a medical test involving the removal of cells or tissues for examination. The tissue is generally examined under a microscope by a pathologist, and can also be analyzed chemically (for example, using PCR or gas chromatography techniques). When only a sample of tissue is removed, the procedure is called an incisional biopsy or core biopsy. When an entire lump or suspicious area is removed, the procedure is called an excisional biopsy. When a sample of tissue or fluid is removed with a needle, the procedure is called a needle aspiration biopsy.

Breast Biopsy

Several methods for breast biopsy now exist. The most appropriate method of biopsy for a patient depends upon a variety of factors, including the size, location, appearance and characteristics of the abnormality.

• Fine Needle Aspiration

(FNA) Fine needle aspiration (FNA) is a percutaneous ("through the skin") procedure that uses a fine needle and a syringe to sample fluid from a breast cyst or remove clusters of cells from a solid mass. With FNA, the cellular material taken from the breast is usually sent to the pathology laboratory for analysis. FNA can also be used by the radiologist or surgeon to drain fluid from a benign cyst. This procedure is called cyst aspiration. A Fine Needle Aspiration procedure is almost painless and takes only a few minutes to perform.

• Core Needle Biopsy

A core needle biopsy is a procedure that removes small but solid samples of tissue using a hollow "core" needle. For palpable (“able to be felt”) lesions, the physician is fixing the lesion with one hand and performing a freehand needle biopsy with the other. In case of non-palpable lesions stereotactic mammography or ultrasound guidance is used. With stereotactic mammography it is possible to pinpoint the exact location of a mass based on images taken from two different angles of the x-ray machine. With ultrasound, the radiologist or surgeon can watch the needle on the ultrasound monitor to help guide it to the area of concern. The needle used during core needle biopsy is larger than the needle used with FNA. The core biopsy needle also has a special cutting edge allowing removal of a bigger sample of tissue. With Core Needle Biopsy a relatively large samples can be removed through a small single incision in the skin. First, the breast area is locally anesthetized with a small amount of anesthetic fluid. Then, the needle is placed into the breast. As with FNA, the radiologist or surgeon will guide the needle into the area of concern by palpating the lump. If the lesion can’t be felt the core needle biopsy is performed under image-guidance using either stereotactic mammography, ultrasound or even magnetic resonance imaging (MRI). A core needle biopsy procedure takes a few minutes to perform and is almost painless. Most patients are able to resume normal activity immediately after the procedure.

• Vacuum Assisted Biopsy

Vacuum Assisted Biopsy is a version of Core Needle Biopsy using a vacuum technique to assist the collection of the tissue sample. The needle normally has a lateral (“from the side”) opening and can be rotated allowing multiple samples to be collected through a single skin incision. The Vacuum Assisted Biopsy procedure is similar to normal Core Needle Biopsy.

• Open Surgical Biopsy

Open Surgical Biopsy means that a large mass or lump is removed during a surgical procedure. Surgical biopsy requires an approximately 3 to 5 centimeters incision and is normally performed in an operating room in sterile conditions. Open surgical biopsy in some cases can be performed with local anesthesia but in most cases general anesthesia may be necessary. Ten years ago, most breast biopsies were open surgical procedures. Today most patients are candidates for less invasive biopsy procedures such as core needle biopsy.

• Minimal Invasive Biopsy

With the Spirotome biopsy system a breast biopsy can be performed easy with minimal pain and with high quality and accurate results. Its unique helix formed cutting mechanism facilitates maximum sample volume through minimal skin incision and also reduces the number of samples necessary to get an accurate result.

The Spirotome is a fully manual biopsy system for biopsy procedures in hospitals or in an outpatient facility. The procedure is performed under local anesthesia, making it more or less painless.

History

One of the earliest diagnostic biopsies was developed by the Arab physician Abulcasim (1013-1107 AD). A needle was used to puncture a goiter, and the material issuing was characterized.

Cancer

When cancer is suspected, a variety of biopsy techniques can be applied. An excisional biopsy is an attempt to remove the entire lesion. When the specimen is evaluated, in addition to diagnosis, the amount of uninvolved tissue around the lesion, the surgical margin of the specimen is examined to see if the disease has spread beyond the area biopsied. "Clear margins" or "negative margins" means that no disease was found at the edges of the biopsy specimen. "Positive margins" means that disease was found, and a wider excision may be needed, depending on the diagnosis. When intact removal is not indicated for a variety of reasons, a wedge of tissue may be taken in an incisional biopsy. In some cases, a sample can be collected by devices that "bite" a sample. A variety of sizes of needle can collect tissue in the lumen (‘’core biopsy’’). Smaller diameter needles collect cells and cell clusters, fine needle aspiration biopsy. Pathologic examination of a biopsy can determine whether a lesion is benign or malignant, and can help differentiate between different types of cancer. In contrast to a biopsy that merely samples a lesion, a larger excisional specimen called a resection may come to a pathologist, typically from a surgeon attempting to eradicate a known lesion from a patient. For example, a pathologist would examine a mastectomy specimen, even if a previous nonexcisional breast biopsy had already established the diagnosis of breast cancer. Examination of the full mastectomy specimen would confirm the exact nature of the cancer (subclassification of tumor and histologic "grading") and reveal the extent of its spread (pathologic "staging").

Precancerous conditions

For easily detected and accessed sites, any suspicious lesions may be assessed. Originally, this was skin or superficial masses. X-ray, then later CT, MRI, and ultrasound along with endoscopy extended the range.

Inflammatory conditions

A biopsy of the temporal arteries is often performed for suspected vasculitis. In inflammatory bowel disease (Crohn's disease and ulcerative colitis), frequent biopsies are taken to assess the activity of disease and to assess changes that precede malignancy.

Biopsy specimens are often taken from part of a lesion when the cause of a disease is uncertain or its extent or exact character is in doubt. Vasculitis, for instance, is usually diagnosed on biopsy.

Kidney disease

Biopsy and fluorescence microscopy are key in the diagnosis of alterations of renal function.

Infectious disease

Lymph node enlargement may be due to a variety of infectious or autoimmune diseases.

Metabolic disease

Some conditions affect the whole body, but certain sites are selectively biopsied because they are easily accessed. Amyloidosis is a condition where degraded proteins accumulate in body tissues. In order to make the diagnosis, the gingival

Transplantation

Biopsies of transplanted organs are performed in order to determine that they are not being rejected or that the disease that necessitated transplant has not recurred.

Fertility

A testicular biopsy is used for evaluating the fertility of men and find out the cause of a possible infertility, e.g. when sperm quality is low, but hormone levels still are within normal ranges.

Commonly biopsied sites

Bone marrow

Since blood cells are formed in the bone marrow, a bone marrow biopsy is employed in the diagnosis of abnormalities of blood cells when the diagnosis cannot be made from the peripheral blood alone. In malignancies of blood cells (leukemia and lymphoma) a bone marrow biopsy is used in staging the disease. The procedure involves taking a core of trabecular bone using a trephine, and then aspirating material.

Gastrointestinal tract

Flexible endoscopy enables access to the upper and lower gastrointestinal tract, such that biopsy of the esophagus, stomach and duodenum via the mouth and the [rectum], colon and terminal ileum are commonplace. A variety of biopsy instruments may be introduced through the endoscope and the visualized site biopsied. Until recently, the majority of the small intestine could not be visualized for biopsy. The double-ballon “push-pull” technique allows visualization and biopsy of the entire gastrointestinal tract. .

Needle core biopsies or aspirates of the pancreas may be made through the duodenum or stomach.

Lung

Biopsies of the lung can be performed in a variety of ways depending on the location.

Liver

In hepatitis, most biopsies are not used for diagnosis, which can be made by other means. Rather, it is used to determine response to therapy which can be assessed by reduction of inflammation and progression of disease by the degree of fibrosis or, ultimately, cirrhosis.

In Wilson's disease, the biopsy is used to determine the quantitative copper level.

Analysis of biopsied material

After the biopsy is performed, the sample of tissue that was removed from the patient is sent to the pathology laboratory. A pathologist is a physician who specializes in diagnosing diseases (such as cancer) by examining tissue under a microscope. When the laboratory receives the biopsy sample, the tissue is processed and an extremely thin slice of tissue is removed from the sample and attached to a glass slide. Any remaining tissue is saved for use in later studies, if required. The slide with the tissue attached is treated with dyes that stain the tissue, which allows the individual cells in the tissue to be seen more clearly. The slide is then given to the pathologist, who examines the tissue under a microscope, looking for any abnormal findings. The pathologist then prepares a report that lists any abnormal or important findings from the biopsy. This report is sent to the physician who originally performed the biopsy on the patient.

See also

Bone marrow examination
Endometrial biopsy
Lymph node biopsy
Skin biopsy

External links

• Mybiopsyinfo.com - What is a biopsy? How is a biopsy examination performed? This website gives you answers to these and many other questions.
• MyBiopsy.org - Information about biopsy results for patients. This site is created by pathologists, the physicians who diagnose cancer and other diseases by looking at biopsies under a microscope.
• RadiologyInfo - The radiology information resource for patients: Biopsy

References