A skin lesion biopsy is the removal of a piece of suspected abnormal skin to diagnose or rule out an illness.
How the Test is Performed
There are several ways to do a skin biopsy. Most procedures can be done in your doctor's office or an outpatient medical office.
Which procedure you have depends on the location, size, and type of lesion. A lesion is an abnormal area of the skin. This can be a lump, sore, or an area of skin color that is not normal.
You will receive some type of numbing medicine (anesthetic) before any type of skin biopsy. Types of skin biopsies are described below.
A shave biopsy is the least invasive method. Your doctor uses a small blade to remove the outermost layers of skin. The area removed includes all or part of the lesion. You do not need stitches. At the end of the procedure, medicine is applied to the area to stop any bleeding. This type of biopsy is often done when a skin cancer is suspected.
A punch biopsy is most often used for deeper skin lesions. Your doctor uses a skin punch tool to remove a small round piece of skin. The area removed is about the size of a pencil eraser. It includes all or part of the lesion. Medicine is put on the area to stop any bleeding. Often, the area is closed with stitches. This type of biopsy is often done to diagnose rashes.
An excisional biopsy is usually done by a surgeon. During the procedure, the entire lesion is removed. Numbing medicine is injected into the area. The entire lesion is removed, going as deep as needed to get the whole area. The area is closed with stitches. If a large area is biopsied, skin graft or flap of normal skin may be used to replace the skin that was removed. This type of biopsy is done when a kind of skin cancer called melanoma is suspected.
An incisional biopsy takes only a piece of a large lesion for examination. Numbing medicine is injected into the area. A piece of the growth is cut and sent to the lab for examination. You may have stitches, if needed. The rest of the growth can be treated after the diagnosis is made.
How to Prepare for the Test
Tell your health care provider:
- About the medicines you are taking, including vitamins and supplements, herbal remedies, and over-the-counter medicines
- If you have any allergies
- If you have bleeding problems or take a blood thinner drug such as aspirin, warfarin, or Plavix
- If you are or think you might be pregnant
Follow your provider's instructions on how to prepare for the biopsy.
How the Test will Feel
There is a brief prick and sting as the anesthetic is injected. The biopsy area may be tender for a few days after the procedure.
Why the Test is Performed
Your doctor may order a skin biopsy if you have signs or symptoms of:
- Chronic or acute skin rashes
- Noncancerous (benign) growths
- Skin cancer
- Other skin conditions
A normal result means that the skin area that was removed is healthy. Doctors call this a negative biopsy result.
What Abnormal Results Mean
The test may reveal skin cancer or a noncancerous (benign) condition. Bacteria and fungi can be identified. The test may also reveal some types of inflammatory skin diseases. Once the diagnosis is confirmed with the biopsy, a treatment plan is usually started.
Risks of a skin biopsy may include:
- Scar (keloids)
You will bleed slightly during the procedure. Tell your provider if you have a history of bleeding problems.
Punch biopsy; Shave biopsy; Skin biopsy; Biopsy - skin
Affleck AG, Colver G. Skin biopsy techniques. In: Robinson JK, Hanke CW, Siegel DM, et al, eds. Surgery of the Skin: Procedural Dermatology. 3rd ed. Philadelphia, PA: Elsevier; 2015:chap 11.
Habif TP. Dermatologic surgical procedures. In: Habif TP. Clinical Dermatology: A Color Guide to Diagnosis and Therapy.6th ed. Philadelphia, PA: Elsevier; 2016:chap 27.
Update Date 7/23/2015
Updated by: Kevin Berman, MD, PhD, Atlanta Center for Dermatologic Disease, Atlanta, GA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.