BIOPSY

A biopsy allows your veterinarian to determine the types of cells in a tissue sample.

• Biopsies are commonly used to determine if growths are cancerous but can also help determine the severity of a disease.
• The tissue removed during a biopsy is examined under a microscope by a veterinary pathologist, a specialist in examining cells and tissue samples.
• Some form of anesthesia is generally required to perform a biopsy.

What Is a Biopsy?
A biopsy is a surgical procedure in which a tissue sample is removed from the body and examined under a microscope. In some cases, only a small sample is removed for analysis. In other cases, several samples may be removed, or an entire growth may be removed and examined.

What Is a Biopsy Used For?
Dogs and cats commonly develop lumps and growths on their skin. Sometimes these lumps are cancerous, but in other cases, they are simply warts or other noncancerous (benign) growths. Examining a lump does not always give your veterinarian enough information to tell whether it is cancerous or not. A biopsy may be recommended to obtain more information about a suspicious lump.

A biopsy can also be used to diagnose a condition or determine the severity of a disease. For example, if an animal has liver disease, a sample of the liver can be removed (during a biopsy) and examined under a microscope to help determine the cause and extent of the liver damage.

How Is a Biopsy Performed?
Some form of anesthesia is generally required to perform a biopsy. Depending on several factors, including where the tissue sample(s) is/are located and how many areas need to be sampled, your veterinarian will decide whether to use local anesthesia, sedation, or general anesthesia. Local anesthesia usually involves injecting a medication in and around an area of the body to make it numb.

If local anesthesia is used, your pet will likely be awake during the biopsy. In contrast, if sedation or general anesthesia is used, the patient is heavily sedated or completely asleep during the procedure. Sometimes, if a growth is on the surface of the skin and is very small, your veterinarian may be able to perform a biopsy using local anesthesia. However, if the area to be biopsied is within the abdomen, for example, or if multiple areas will be biopsied, general anesthesia is usually recommended.

Your veterinarian has a few options when deciding how to perform a biopsy and how much tissue to remove. In an incisional biopsy, a small sample of tissue is removed from a larger mass. In an excisional biopsy, the entire growth is removed and submitted for biopsy.

Once the tissue is removed, your veterinarian will submit it to a diagnostic laboratory. There, a veterinary pathologist (a specialist at examining cells and tissue samples) will examine the tissue under a microscope to make a diagnosis. Results are generally available within several days.  

What Are the Benefits and Risks of a Biopsy?
Biopsies are very important for helping to confirm a diagnosis. With many types of cancers, early diagnosis is helpful for determining the course of treatment and can help increase the chance of survival. Biopsies can also help to confirm causes of other conditions, including skin lesions as well as diseases of the kidneys, liver, or bone marrow.

Your veterinarian will take many precautions to help ensure that your pet is safe during the biopsy and fully recovers afterward. To help reduce the risk of complications associated with surgery or anesthesia, your veterinarian may give your pet a full physical examination and check your pet’s blood work before the biopsy.

Biopsies are very safe, routine procedures. The risks associated with a biopsy depend on several factors, including the overall health of the patient, the location of the area to be biopsied, and how many samples are taken. Be sure to discuss any questions or concerns with your veterinarian.