A skin lesion biopsy is when a small amount of skin is removed so it can be examined. The skin is tested to look for skin conditions or diseases. A skin biopsy can help your health care provider diagnose or rule out problems such as skin cancer or psoriasis.
How the Test is Performed
There are several ways to do a skin biopsy. Most procedures can be done in your provider's office or an outpatient medical office. It will take about 15 minutes.
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.
Before a biopsy, your provider will numb the area of skin so you don't feel anything. The different types of skin biopsies are described below.
Your provider uses a small blade or razor to remove or scrape the outermost layers of skin.
Your provider will remove all or part of the lesion.
You will not need stitches. This procedure will leave a small indented area.
This type of biopsy is often done when a skin cancer is suspected.
Your provider uses a skin punch tool to remove deeper layers of skin.
The area removed is about the shape and size of a pencil eraser.
It includes all or part of the lesion. You may have stitches to close the area.
This type of biopsy is often done to diagnose rashes.
A surgeon uses a surgical knife (scalpel) to remove the entire lesion. This may include deep layers of skin and fat.
The area is closed with stitches to place the skin back together.
If a large area is biopsied, the surgeon may use a skin graft or flap to replace the skin that was removed.
This type of biopsy is done when a kind of skin cancer called melanoma is suspected.
This procedure takes a piece of a large lesion.
A piece of the growth is cut and sent to the lab for examination. You may have stitches, if needed.
After diagnosis, the rest of the growth can be treated.
This procedure allows skin cancer to be removed with less damage to the healthy skin around it.
It is most often done to remove skin lesions on the eyelids, nose, ears, lips, or hands.
How to Prepare for the Test
Tell your provider:
About the medicines you are taking, including vitamins and supplements, herbal remedies, and over-the-counter medicines
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.
Why the Test is Performed
Your provider may order a skin biopsy:
To diagnose the cause of a skin rash
To make sure a skin growth or skin lesion is not skin cancer
The tissue that was removed is examined under a microscope. Results are most often returned in a few days to a week or more.
If a skin lesion is benign (not cancer), you may not need any further treatment. If the whole skin lesion was not removed at the time of biopsy, you and your provider may decide to completely remove it.
What Abnormal Results Mean
Once the biopsy confirms the diagnosis, your provider will start a treatment plan. A few of the skin problems that may be diagnosed are:
The goal is to keep the area clean and dry. Be careful not to bump or stretch the skin near the area, which can cause bleeding. If you have stitches, they will be taken out in about 3 to 14 days.
If you have moderate bleeding, apply pressure to the area for 10 minutes or so. If the bleeding does not stop, call your provider right away. You should also call your provider if you have signs of infection, such as:
More redness and swelling
Drainage coming from or around the incision that is thick, tan, green, or yellow, or smells bad (pus)
Once the wound heals, you may have a scar.
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, ed. Clinical Dermatology: A Color Guide to Diagnosis and Therapy. 6th ed. Philadelphia, PA: Elsevier; 2016:chap 27.
Richard J. Moskowitz, MD, dermatologist in private practice, Mineola, NY. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team. Editorial update: 03/09/2016.