What Is a Biopsy?

A biopsy is a medical procedure that involves removing a small sample of tissue or cells so it can be examined under a microscope. It can help diagnose a condition and determine its severity so that the right treatment can be prescribed. A biopsy can also monitor how well you respond to a specific type of treatment.

There are different types of biopsies, some of which are performed surgically and others of which may involve a needle, imaging tests, or an endoscope. If your healthcare provider recommends a biopsy, it is because less invasive methods of diagnosis cannot confirm (or exclude) a suspected disease or medical condition.

This article will explore the purpose, uses, and types of biopsies commonly used in medicine. It will also explain how these results are interpreted by specialists known as medical pathologists.

Medical Uses

When people hear the word "biopsy," they often assume that to mean cancer is involved. And, while biopsies are often central to the diagnosis of cancer, they have so many other purposes.

Among the conditions that may require a biopsy are:

• Autoimmune diseases (such as celiac disease)
• Cancer (including blood cancer and skin cancer)
• Endometriosis
• Heart disease (including vascular diseases and heart failure)
• Infectious diseases (such as meningitis or pneumonia)
• Gastrointestinal disorders (such as inflammatory bowel disease)
• Kidney disease (including unexplained kidney failure)
• Male infertility (testicular biopsy)
• Liver disease (including cirrhosis and liver failure)
• Lung disease (including COPD and pleural effusion)
• Neurological conditions (such as multiple sclerosis)
• Organ transplants (to identify signs of organ rejection)

A biopsy can be used to diagnose many diseases and medical conditions. Some diseases, including many solid-tumor cancers, can only be definitively diagnosed with a biopsy.

Who Performs a Biopsy?

Depending on which tissues or cells are being biopsied, the procedure can be performed by any number of certified physicians, including:

• Surgeons, both general surgeons and specialized
• Radiologists, who specialize in taking medical images
• Gastroenterologists, who specialize in the digestive tract
• Hematologists, who specialize in diseases of the blood
• Dermatologists, who specialize in diseases of the skin
• Interventional cardiologists

Types of Biopsies

There are a variety of different biopsy techniques uses by surgeons and other physicians. Some are performed on their own, while others are performed as part of other diagnostic or treatment-related procedures.

Fine-Needle Aspiration

A fine-needle aspiration (FNA) involves the removal of tissue or fluid using a thin needle. A local anesthetic is sometimes used to numb the area before the insertion of the needle. FNA is often used to obtain tissue or cells from lymph nodes, cysts, nodules, abscesses, or tumors.

Core Needle Biopsy

Core needle biopsy, or simply core biopsy, is used when a larger amount of tissue is needed than can be obtained from FNA. As per its name, it involves a larger needle with a hollow core. Sedation is sometimes required along with a local anesthetic.

CT-Guided Percutaneous Biopsy

CT-guided percutaneous biopsy is a procedure in which the placement of a needle is directed by computed tomography (CT). CT is an imaging tool that composites a series of X-ray images in "slices" to create a three-dimensional representation of a body part.

Interventional radiologists perform CT-guided biopsies. Some procedures may involve real-time CT images viewed on a digital monitor.

Stereotactic Biopsy

A stereotactic biopsy is similar to a CT-guided biopsy in that it uses imaging tools to direct the placement of a core needle into a tumor within a three-dimensional space. A stereotactic biopsy utilizes 3D mammography, a type of breast imaging study using low-dose radiation, to accurately locate the position of a breast tumor.

Punch Biopsy

A punch biopsy utilizes a compact tubular blade, similar in appearance to an apple corer, to obtain a deep sample of tissue. A local anesthetic is applied before the device is screwed into the skin to obtain a full-thickness specimen.

Shave Biopsy

A shave biopsy involves the removal of a layer of skin using a small blade and a microscope. It is a reasonably safe way to diagnose melanoma without risking the spread of cancer. A local anesthetic or topical numbing agent may be used, but stitches are unnecessary.

Bone Marrow Biopsy

A bone marrow biopsy involves the removal of bone marrow, blood, and a small piece of bone from the sternum (breastbone) or iliac crest (upper part of hip bone). It typically involves FNA but may sometimes require a core biopsy.

Endoscopic biopsy

An endoscopic biopsy is one in which a tissue sample is obtained when examining an internal structure of the body with an endoscope. It may be performed under monitored anesthesia (which induces "twilight sleep") or general anesthesia (which puts you fully to sleep).

An endoscope is a long thin tube with a fiber-optic camera at the end that is inserted either into an orifice (such as the mouth or anus) or through a hole a small incision. Examples include a colonoscope to view the colon, a cystoscope to view the bladder, a bronchoscope to view the lungs, and an hysteroscope to view the uterus.

During the visual examination, a cutting or pinching device can be fed through the neck of the scope to obtain the tissue sample.

Open Biopsy

An open biopsy is a surgical procedure in which a large incision is made to obtain a tissue sample. It is performed when the tumor or mass is larger than can be obtained with laparoscopic (keyhole) surgery. An open biopsy is often considered in cases of lung, breast, or liver cancer.

A type of open biopsy, called a wedge biopsy, may be performed to obtain a large wedge-shaped section of skin, lung, or liver tissue.

Sentinel Lymph Node Biopsy

A sentinel lymph node biopsy is a surgical procedure in which a lymph node near a cancerous tumor is removed to see if cancer spread beyond the tumor. A radioactive dye is injected near the tumor prior to the surgery. The lymph node that picks up the dye first is the one that is removed.

Excisional and Incisional Biopsy

An excisional biopsy is a surgical procedure in which an entire tumor is removed, while an incisional biopsy only involves the partial removal of a tumor. Excisional biopsies are typically performed when there is a risk that cancer may spread if a tumor is disrupted (such as may occur with melanoma or testicular cancer).

Liquid Biopsy

A liquid biopsy involves the testing of a blood sample to look for circulating cancer cells or pieces of DNA from cancer cells. It can be useful at detect cancer at an early stage and to see how well a cancer treatment is working. No preparation is needed as the biopsy only involves a blood draw.

Interpretation

After the sample is obtained from a biopsy, it is sent to the lab for review by a pathologist. There are several procedures the pathologist may use depending on the suspected disease or condition, including:

• Gross pathology: The examination of a biopsied tissue or organ by the naked eye to visually assess if there are any abnormalities
• Histopathology: The evaluation of tissues under the microscope to ascertain if there are any microscopic abnormalities
• Cytopathology: The examination of tissues on a cellular level, often involving stains and chemicals to highlight cell structures
• Dermatopathology: A specialized field of pathology devoted to the examination of skin and underlying structures
• Hematopathology: A specialized field devoted to the examination of blood cells and organs that help produce blood cells (including bone marrow, lymph nodes, the thymus gland, and spleen)
• Neuropathology: A specialized field of pathology devoted to the examination of nerve tissues and cells
  

Summary

A biopsy is a test that involves the extraction of cells or tissues for examination in a lab. The biopsy can be used to determine the presence or extent of a disease. They are commonly performed by surgeons and interventional radiologists but can also be done by specialists such as dermatologists and gastroenterologists.

There are different biopsy techniques, some of which are minimally invasive (involving needles or scrapers) and others performed during an endoscopic or surgical procedure. The biopsied tissues or cells are evaluated by a medical pathologist who specializes in the study of body tissues and body fluids.

A Word From Verywell

Being told you need a biopsy can be stressful, but it doesn't necessarily mean your condition is more serious. In some cases, a biopsy may be needed to exclude other causes of your symptoms or because the initial tests were simply inconclusive.

Even if a biopsy confirms a more serious disease, like cancer, the information provided by the biopsy is invaluable in helping select the best treatments possible.

If you need a biopsy, ask as many questions as you need to understand why it is recommended and what the pathology report means. Take it one step at a time and try not to jump to any conclusions until the results are received.