Getting Tested for Skin Cancer? Here’s How To Prepare for a Punch Biopsy (2024)

A punch biopsy is a procedure that checks for signs of skin cancer—the most common type of cancer in the United States. The condition occurs when cancer cells form in the skin, often due to ultraviolet (UV) light from too much sun exposure.

Your healthcare provider may recommend a punch biopsy if they suspect that you are at risk of skin cancer or notice signs of the condition. Common symptoms include an irregular mole, a sore that doesn’t heal, or a red rash that doesn’t resolve.

A dermatologist (a medical doctor who specializes in the diagnosis and treatment of skin disorders) usually performs a punch biopsy. They will use a circular tool that looks like a tiny cookie cutter to take a sample of your skin. Once they obtain a sample, they will send it to a lab for a pathologist (a medical doctor who specializes in diagnosing diseases) to examine and make a diagnosis.

The purpose of a punch biopsy is to determine if you have skin cancer or another skin condition. If you notice a concerning area of skin, your dermatologist may recommend a punch biopsy. If you have a very small area of skin cancer, your provider may be able to remove the entire cancerous growth with a punch biopsy. This is sometimes possible in cases of basal cell carcinoma and squamous cell carcinoma—two of the most common types of skin cancer.

How Does It Work?

During a punch biopsy, your dermatologist will numb your skin before removing part of the skin tissue. Once your provider obtains a tissue sample, they will send it to a lab for a pathologist to review for cancer cells.

Before the Test

You will likely go to your dermatologist’s office for your punch biopsy. When you arrive for your appointment, you will be asked to fill out screening questionnaires and a treatment waiver. If your dermatologist sent you the forms ahead of time, bring them with you.

You may be asked to change into a hospital gown for the procedure, depending on where on the body your biopsy is taking place. Your dermatologist will then inject numbing medicine around the skin lesion, which may sting at first. You will not be sedated for the biopsy.

During the Test

Once the area of the skin is numb, your dermatologist will place a circular tool over the skin lesion. They will press down and rotate the tool to cut a small circle of skin tissue. Generally, the sample is about the size of a pencil eraser. They will then use an additional tool to lift the sample out of the skin.

After the punch biopsy is complete, your dermatologist will likely place one or two stitches. Once the bleeding has stopped, they will cover the area with a sterile bandage.It is common to feel pressure during a punch biopsy but you should not expect to feel pain. You will not be sedated or drowsy and will be able to communicate with your healthcare team the entire time.

Getting Tested for Skin Cancer? Here’s How To Prepare for a Punch Biopsy (1)

In most cases, you will be able to go home after your punch biopsy. After your biopsy, your provider will send your tissue sample to a lab for a pathologist to review. It may take up to two weeks to get your results back from the pathologist. Once your results are ready, your provider will call you or set up an appointment to discuss the results.

Risks and Precautions

Every medical test comes with certain risks and possible side effects. Risks of a punch biopsy may include the following:

Infection: It is possible to experience an infection at the biopsy site. Signs of infection may include redness, swelling, pain, and pus.
Bleeding: Bleeding after a punch biopsy is possible, especially if your provider did not sew the edges of the skin together with stitches.
Bruising: It is normal to notice some bruising at your biopsy site as it heals.
Soreness: Your skin in and around the biopsy site may feel sore for a few days.

Going in for a punch biopsy can feel scary, but knowing what to expect may help ease some stress. Consider the following factors when preparing for a punch biopsy:

Location: In most cases, dermatologists perform punch biopsies in their outpatient clinics.
Attire: Plan to wear loose, comfortable clothing to your biopsy appointment. Make sure your skin lesion is easily accessible. Your provider may recommend changing into a hospital gown to prevent any blood from getting on your clothes.
Food and drink: In most cases, you can eat and drink normally before your punch biopsies. Skin biopsies usually do not require anesthesia, so you will not need to fast before your appointment.
Medications: If you are currently taking any medication that causes your blood to thin such as aspirin, your dermatologist may recommend stopping it before your biopsy.
Items to bring: When going to your punch biopsy appointment, plan to bring your driver’s license or identification card, insurance information, and any forms that were mailed to you.
Emotional support: You will likely be able to drive yourself home after your skin biopsy. If you would like to bring a loved one for support, ask your healthcare team where your friend or family member can wait during your biopsy.

Cost and insurance: Before your biopsy, plan to call both your insurance company and hospital billing department to ask how much insurance will cover or how much you may need to pay out-of-pocket.

Results

Your punch biopsy results will indicate if you have skin cancer, a skin condition, or a skin infection. When the results are ready, the pathologist will send a report to your dermatologist. Your provider will then contact you via the phone, email, or an electronic medical record.

The results of your biopsy will either be normal, abnormal, or inconclusive. Here is what they mean:

Normal result: A normal result means that there were no cancer cells in your sample, and the pathologist does not believe you have cancer or another skin condition.
Abnormal result: An abnormal result means that the pathologist either saw cancer cells or a sign of disease in your tissue sample. The next step will be to work with your dermatologist on further testing and a treatment plan.
Inconclusive result: An inconclusive test result means that the pathologist did not detect cancer but also cannot rule it out. If you receive an inconclusive result from a punch biopsy, your provider may recommend another type of skin biopsy.

A Quick Review

A punch biopsy is a type of skin biopsy used to diagnose skin cancer, skin conditions, and skin infections. A dermatologist usually performs a punch biopsy. Your provider may recommend a punch biopsy if they see possible signs of skin cancer including a sore that doesn’t heal or an abnormal mole. Generally, a punch biopsy doesn't cause too much pain and you can expect to get your biopsy results back within two weeks.