What Is A Biopsy? What Are Biopsies Used For?

A biopsy is a medical procedure that involves taking a small sample of tissue so that it can be examined under a microscope for purposes of diagnosis.

The term ‘biopsy’ is often used to refer to the act of taking the sample and the tissue sample itself.

A biopsy may be done, for example, because of concern about cancer. In the case of certain signs and symptoms or if the doctor has identified an area of concern, a biopsy is required to determine whether there is cancer or some other condition. The physical exam, imaging, endoscopy, and laboratory tests may indicate that something is abnormal. They are helpful in detecting masses or areas of abnormality. However, they alone cannot differentiate cancerous cells from noncancerous cells. For the majority of cancers, the only way to make a definitive diagnosis is to use a biopsy to collect cells for closer examination.

In a biopsy, the doctor removes a sample of tissue from the abnormal area or may remove the whole tumor. A specialist trained to examine such tissues is called a pathologist. Then, the pathologist examines the tissue under a microscope. If cancer is present, the pathologist can usually tell what kind of cancer it is and may be able to judge whether the cells are likely to grow slowly or quickly.

According to Medilexicon’s medical dictionary:

A biopsy is: “The process of removing tissue from patients for diagnostic examination.

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Types of biopsy

A tissue sample can be taken from almost anywhere on the body, such as the skin, stomach, kidneys, liver, and lungs.

A number of different types of biopsy can be used to help identify a wide range of different health conditions. Types of biopsy include:

• Capsule biopsy: used when a sample from the intestine lining needs to be taken.
• Endoscopic biopsy: where a medical instrument known as an endoscope is used to take a tissue sample.
• Excisional biopsy: where surgery is used to take a larger section of tissue.
• Needle biopsy: for obtaining tissue from the body’s organs, or from tissue underneath the skin.
• Punch biopsy: for diagnosing skin conditions.
• Scraping cells: removing cells from the surface layer of tissue, such as from the inside of the mouth, or from inside the cervix.

The way the biopsy is carried out will depend on where the tissue sample is being taken from.

What are biopsies used for?

Biopsies are used to identify abnormal cells. The result of a biopsy can often help healthcare professionals to diagnose a wide range of conditions including cancer, peptic ulcers (ulcers that affect the digestive system), hepatitis (inflammation of the liver), kidney disease, and endometriosis (where cells that usually line the womb are found elsewhere in the body). A biopsy can also be used to measure the severity of a condition. For example, how severely an organ, such as the liver, is inflamed.

Biopsies are commonly used to check whether a breast lump is benign (non-cancerous) or malignant (cancerous).

The cells will be closely examined under a microscope to see whether or not they appear abnormal, and to check for any unusual cell activity. The cells may also be tested using various chemicals to see how they respond. The type of tests that are used will depend on the medical conditions that are being investigated.

Bone marrow biopsy

A bone marrow biopsy may be recommended if an abnormality in the blood is detected. The bone marrow is where the body produces blood cells. Analyzing a sample of bone marrow may reveal what is causing the blood problem.

Bone marrow biopsies are carried out for a number a different reasons including a low or high number of red blood cells (anemia), a low or high number of white blood cells (leucopenia), or a low or high number of platelets (blood-clotting cells).

A number of different health conditions may be responsible for these types of blood abnormalities, such as leukemia (cancer of the bone marrow and white blood cells), or other types of blood disorders. Samples of blood marrow are also sometimes taken to check how well treatment for leukemia is working, or to determine how far certain types of cancer have progressed.

During a bone marrow biopsy, the doctor draws a sample of bone marrow out of the back of the hip bone using a long needle.

In some cases, marrow from other bones in the body may be analyzed. Bone marrow biopsy is commonly used to diagnose a variety of blood problems both noncancerous and cancerous, including blood cancers, such as leukemia, lymphoma and multiple myeloma. The patient receives a local anesthetic before a bone marrow biopsy in order to minimize discomfort during the procedure.

Endoscopic biopsy

During endoscopy, a thin, flexible tube with a light is used to see structures inside the body. Special tools are passed through the tube to take a small sample of tissue to be analyzed.

The type of endoscopic biopsy depends on where the suspicious area is located. Tubes used in an endoscopic biopsy can be inserted through the mouth, rectum, urinary tract or a small incision in the skin. Examples of endoscopic biopsy procedures include:

• Cytoscopy to collect tissue from the inside of the bladder.
• Bronchoscopy to get tissue from inside the lung.
• Colonoscopy to collect tissue from inside the colon.

Depending on the type of endoscopic biopsy, the patient may receive a sedative or anesthetic before the procedure.

Capsule biopsy

A capsule biopsy is an alternative to an endoscopic biopsy. It is used when a sample of the lining of the intestine needs to be taken.

During a capsule biopsy, the patient is given a small capsule to swallow that is attached to a thin tube. X-ray images will be used to determine when the capsule has reached the correct point in the gut. When it has reached the correct point, pressure is created in the tube, so that a small piece of the intestine lining is sucked into the capsule, before being removed from the body.

Needle biopsy

During a needle biopsy, a special needle is used to extract cells from a suspicious area. A needle biopsy is often used on tumors that can be felt through the skin, such as suspicious breast lumps and enlarged lymph nodes. When combined with an imaging procedure, such as X-ray, needle biopsy can be used to collect cells from a suspicious area that cannot be felt through the skin.

Needle biopsy procedures include:

• Fine-needle aspiration. During fine-needle aspiration, a long, thin needle is inserted into the suspicious area. A syringe is used to draw out fluid and cells for analysis. A breast lump biopsy is known as a fine-needle aspiration biopsy. The needle is inserted into the lump and a sample of tissue is taken for testing.
• Core needle biopsy. A larger needle with a cutting tip is used during core needle biopsy to draw a column of tissue out of a suspicious area.
• Vacuum-assisted biopsy. During vacuum-assisted biopsy, a suction device increases the amount of fluid and cells that is extracted through the needle. This can reduce the number of times the needle must be inserted to collect an adequate sample.
• Image-guided biopsy. Image-guided biopsy combines an imaging procedure, such as X-ray, computerized tomography (CT) or ultrasound, with a needle biopsy. Image-guided biopsy allows access to suspicious areas that cannot be felt through the skin, such as abnormalities on the liver, lung or prostate. Using real-time images, the doctor is positive that the needle reaches the correct spot.

A local anesthetic to numb the area being biopsied is given in order to minimize the pain.

A thicker, hollow needle is used for taking biopsies of organs, such as the liver, or kidneys. The patient is asked to breathe in and hold their breath while the needle is inserted into the abdomen. It takes a few seconds for a small sample of tissue to be taken. A local anesthetic will usually be used for this type of biopsy because the patient needs to be awake in order to breathe in.

Skin biopsy

A skin biopsy removes cells from the surface of the body. A skin biopsy is used most often to diagnose skin conditions, including cancers, such as melanoma. The type of skin biopsy depends on the type of cancer suspected and the extent of the suspicious cells. Skin biopsy procedures include:

• Shave biopsy. A tool similar to a razor is used to scrape the surface of the skin. Stitches are usually not needed after a shave biopsy.
• Punch biopsy. A circular tool is used to remove a small section of the skin’s deeper layers. A punch biopsy extends about 1/4-inch (about 6 millimeters) deep. Stitches are needed to close the wound.
• Incisional biopsy. A scalpel is used to remove a small area of skin. The need for stitches to close the biopsy site depends on the amount of skin removed.
• Excisional biopsy. Excision means ‘cutting out’. An entire lump or an entire area of abnormal skin is removed. Stitches are likely to be needed to close the biopsy site.

A local anesthetic to numb the biopsy site is given before the procedure. A spray-on solution may temporarily numb an area of the skin before a shave biopsy. For a more extensive skin biopsy, a shot of medication may be given to numb the area.

Surgical biopsy

If the cells cannot be accessed with other biopsy procedures or if other biopsy results have been inconclusive, a surgical biopsy may be recommended. During a surgical biopsy, a surgeon makes an incision in the skin to access the suspicious area of cells. Examples of surgical biopsy procedures include surgery to remove a breast lump for a breast cancer diagnosis and surgery to remove a lymph node for a lymphoma diagnosis.

Local anesthetics may be given to numb the area of the biopsy. Some surgical biopsy procedures require general anesthesia to make the patient unconscious during the procedure. A stay in the hospital may be required for observation after the procedure.

Biopsy analysis and results

After the tissue sample is obtained, it is sent to a laboratory for analysis. The sample may be chemically treated or frozen and sliced into very thin sections. The sections are placed on glass slides, stained to enhance contrast. They are studied under a microscope by a person who specializes in examining body tissues (pathologist) or a specialist in blood and blood-forming tissues (hematologist), or both.

The results help determine whether the cells are cancerous. If the cells are cancerous, the biopsy results can tell the doctor where the cancer originated and the type of cancer.

A biopsy also helps doctors determine how aggressive the cancer is and the cancer’s grade. The grade is usually expressed as a number on a scale of 1 to 4. It is determined by how biopsied cancer cells look under the microscope.

Grade 1 or low-grade cancers, are generally the least aggressive and grade 4 or high-grade cancers, the most aggressive. This information may help guide treatment options. Other tests on the cancer cells can also help to guide treatment choices.

In certain cases, during surgery a pathologist examines the sample of cells immediately and results are available to the surgeon within minutes. But in most cases, the results of the biopsy are available in one or two days. Some samples may need more time to be analyzed.

Testing a tissue sample

After the tissue sample has been taken, it will be sent to a laboratory so that it can be examined under a microscope and the tissue’s cells can be tested.

Cells are the ‘building blocks’ that make up the body. By closely examining them, scientists can see whether they are normal or abnormal. Cancerous cells, for example, look and behave differently from normal cells. After a visual examination, chemical, or genetic, tests can also be carried out on the tissue sample.

Pre-natal biopsy

Tests for cystic fibrosis and other genetic conditions can even be carried out on a cell sample that is taken from an unborn baby. The cell sample is taken from the placenta using a pre-natal biopsy called chorionic villus sampling (CVS).

During CVS, a small piece of the placenta is removed using a very fine needle that is passed through the abdomen (stomach) using ultrasound to guide it. Once a cell sample has been obtained, a chromosome (genetic) analysis will be carried out.

This can determine whether the gene that is responsible for cystic fibrosis is present. It usually takes between 10 to 14 days for CVS test results to become available. The results can be used to help parents decide whether they wish to terminate a pregnancy or continue with it.

Scraping cells

In some cases, scraping cells from the surface layer of tissue, such as from inside the mouth, is enough to provide a suitable sample for examination. This is known as ‘scraping biopsy’. It can sometimes be uncomfortable, but it is not painful and an anesthetic is not required.

A cervical screening test is a procedure where a spatula, or small brush-like instrument, is used to gently remove a sample of cells from a woman’s cervix. The cells are then examined under a microscope for any abnormal changes (dysplasia).

If the cells display abnormal changes, it may mean that they are cancerous, or that there is an increased likelihood that that they will become cancerous.

Recovering from a biopsy

Biopsies can often be carried out as outpatient procedures using local anesthetic. In such cases, there is no need to stay in hospital overnight.

Some types of biopsy, such as those that involve taking a tissue sample from an internal organ, will require a general anesthetic. If a general anesthetic is used, the patient may need to stay in hospital overnight.

After having a biopsy, there is usually no pain. However, if a sample was taken from a major organ, such as the liver, or from the bone marrow, there can be a dull ache or a slightly uncomfortable feeling. Painkillers can be prescribed in order to relieve this.

If an incision (cut) is required in order to remove a tissue sample, the wound may need to be closed using stitches. A dressing may be put on the wound.

In some cases where tissue has been taken from an important organ, such as the liver, or kidneys, a stay in hospital for a few hours after the procedure may be needed. This is so that the patient can rest and hospital staff can ensure that there is no internal bleeding, although, it is very rare for serious bleeding to occur following a biopsy.

Women who have had samples taken from their reproductive system, such as their womb lining, or cervix may experience a little light vaginal bleeding. Men who have had a prostate biopsy may have blood in their urine.

Biopsy results

How quickly the results of the biopsy are available will depend on the hospital and the urgency of the case.

The results of routine cervical smear tests usually take between 10 to14 days to become available. Results of biopsies that are carried out because of suspicion of a serious condition, such as cancer, may be available within a few days.

In cases where a biopsy is performed during surgery, a result is often available within minutes so that the right treatment can be given while the surgery is in progress.

A GP, hospital consultant, or practice nurse, will give the results and will explain what they mean.

Sometimes, a biopsy will not be conclusive, which means that it has not produced a definitive result. If this is the case, the process may need to be repeated, or further tests may be required in order to double-check the diagnosis.

Written by Stephanie Brunner (B.A.)
Copyright: Medical News Today