Biopsy

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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.

Contents 1 History 2 Cancer 3 Precancerous conditions 4 Inflammatory conditions 4.1 Kidney disease 4.2 Infectious disease 4.3 Metabolic disease 4.4 Transplantation 4.5 Fertility 5 Commonly biopsied sites 5.1 Bone marrow 5.2 Gastrointestinal tract 5.3 Lung 5.4 Liver 6 Analysis of biopsied material 7 See also 8 External links 9 References

[edit] 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. ^[1]

[edit] 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 biology. ^[2] 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").

[edit] 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.

[edit] 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. ^[3]

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.

[edit] Kidney disease

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

[edit] Infectious disease

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

[edit] 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

[edit] 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.

[edit] 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. ^[4]

[edit] Commonly biopsied sites

[edit] 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.

[edit] 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. ^[5].

Needle core biopsies or aspirates of the pancreas may be made through the duodenum or stomach.^[6]

[edit] Lung

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

[edit] 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.

[edit] 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.

[edit] See also

Bone marrow examination
Endometrial biopsy
Lymph node biopsy
Skin biopsy

[edit] External links

• 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

[edit] References

1. ^ Anderson, J. B., Webb, A.J.: Fine-Needle Aspiration Biopsy and the Diagnosis of Thyroid Cancer. British Journal of Surgery 74:292-6, 1987
2. ^ Sausville, Edward A. and Longo, Dan L.: Principles of Cancer Treatment: Surgery, Chemotherapy, and Biologic Therapy in Harrison's Principles of Internal Medicine, 16th Ed. Kaspar, Dennis L. et al., editors. p.446 (2005)
3. ^ Friedman, S. and Blumberg, R.S.: Inflammatory Bowel Disease in Harrison's Principles of Internal Medicine, 16th Ed. Kaspar, Dennis L. et al., editors. pp. 1176-1789 (2005)
4. ^ Mens health - Testicular Biopsy
5. ^ Saibeni, S., Rondonotti, E., Iozzelli, A., Spina, L., Tontini, G.E., Cavallaro, F., Ciscato, C., de Franchis, R., Sardanelli, F., Vecchi, M.: Imaging of the Small Bowel in Crohn's Disease: A Review of Old and New Techniques World Journal of Gastroenterology 13(24): 3279-87, 2007
6. ^ Iglesias-Garcia, J., Dominguez-Munoz, E., Lozano-Leon, A., Abdulkader, I., Larino-Noia, J., Antunez, J., Forteza, J.: Impact of Endoscopic Ultrasound-Guided Fine Needle Biopsy for Diagnosis of Pancreatic Masses. World Journal of Gastroenterology 13(2): 289-93, 2007