
Overview
This module describes how to use a punch biopsy to take an
incisional
removes part of the lesion
or
excisional
removes the entire lesion
sample of the skin, including the epidermis, dermis, and subcutaneous tissue.
Indications
Because punch biopsies sample deeper tissues, they are most suited to diagnosing lesions where dermal or subcutaneous tissue is required.
Inflammatory lesions & panniculitis
Bullous lesions
Large dysplastic or complex nevi that cannot be excised
Scalp or hair follicle samples
Contraindications
Sites with superficial large vessels or other vital structures
Lesions better sampled by other methods
Lesions that do not require sampling for diagnosis and management e.g. classical atopic eczema
Weigh up the risks and benefits in patients with coagulopathy
Patient information & consent
How do I explain this procedure?
“I need to take a sample of your skin lesion to find out what it is. The method is called a punch biopsy. I use a punch tool to take a small, round sample of the skin and underlying tissue. I will close the wound with a stitch afterwards.”
What can my patient expect?
“I will give you an injection so that you will not feel me taking the sample. You may feel tugging and working in the area, but it will not be painful. The test results may take a few days
or longer
Histology often takes 6 weeks for results. If urgent, call the pathologist directly to discuss and expedite.
after which I will contact you with the diagnosis.”
What is my patient’s role?
“Let me know if you have any allergies or a bleeding tendency, or use blood thinners. Fearing blood or needles is normal, but tell me if you have fainted from it. Keep still while I take the sample. Afterwards, keep the plaster on for at least a day, and come back to remove the stitch in x days.”
Preparation
Prepare a trolley with equipment.

Documentation
Patient notes
Patient labels
Histology forms
Equipment
Non-sterile gloves
Alcohol-based hand rub
- Sharps containerSharps container
If a sharps container is not within arm's length, use a kidney dish or other hard container to temporarily hold used sharps and to carry them to the sharps container for disposal.
- Skin disinfectantSkin disinfectant
Commonly used preparations include 0.5-2% chlorhexidine in 70% alcohol (Steriprep), or 10% povidone iodine. There is no consensus on the superiority of one agent above another. Caution: chlorhexidine solutions may be associated with burns and skin breakdown in infants < 2 months old.
- A punch biopsy toolA punch biopsy tool
Select the right size for the lesion you are sampling. 2-6 mm are most commonly used.
A suture pack and suturing supplies
- Silver nitrate stickSilver nitrate stick
Ideally, have cautery available, Monsel's solution (ferric subsulfate) and aluminium chloride. Monsel's solution can rarely cause tattooing. Aluminium chloride slows wound healing. Silver nitrate can also cause tattooing.
or other haemostatic agents
A 3-5 ml syringe, aspiration needle (preferably blunt fill), and an injection needle
Lignocaine with adrenaline
An alcohol swab
A gauze dressing and transparent film dressing
Specimen jar and formalin
Site and Positioning
The patient should be positioned reclining or supine with the lesion within easy reach.
Identify the area to be sampled
When there are several areas to choose from, select an early lesion or one that is well advanced. Sample larger lesions near the edge of an advancing border. Include the most raised or darkly pigmented area.
Identify Langer Lines
If you do not have a chart indicating
Langer lines

, determine in which direction these lines lie at the biopsy site. Pinch the skin at the site, trying in two directions perpendicular to each other. The direction which produces the most wrinkles is the direction of the Langer lines in this area. When performing the punch biopsy, stretch the skin in a direction perpendicular to these lines, so that the end result is an elliptical wound aligned with the lines. This facilitates easy closure or healing by secondary intent.
Procedure
Follow medical asepsis with non-sterile gloves.
Draw up 2-3 ml lignocaine with adrenaline.
Open the suture pack and pour skin disinfectant into the well.
Perform hand hygiene and don gloves.
- CleanClean
Start in the middle and clean in concentric circles outward.
the skin with cleaning solution.
Anaesthetise the site with lignocaine.
Tense the skin perpendicular to Langer lines with your non-dominant hand.
- Insert the punchInsert the punch
Insert until there is a loss of skin tension, indicating full thickness insertion.
You want to get to at least the level of the dermal-subcutaneous tissue interface., using rotational movements.
Remove the punch.
Elevate the sample using the
tip of the anaesthesia needletip of the anaesthesia needleForceps should not be used as they create crush artifact.
with your non-dominant hand.
Cut off the sample with scissors below the level of the dermis.
Use the silver nitrate stick to stop bleeding if necessary.
- If necessaryIf necessary
Generally only necessary in cosmetically critical sites, or in punch biopsies of 6 mm or greater in diameter. A 5-0 suture is usually used in non-facial areas and a 6-0 in facial areas.
, insert a suture to close the wound.
Apply a gauze pad and transparent film dressing.
Label a specimen jar of formalin, and send the sample in it to the laboratory with a histology form.
Dispose of medical waste safely.
Record completion of the procedure in patient notes.
Troubleshooting
I’ve encountered pigmented tissue at the base of the specimen.
Continue to punch well into the subcutaneous fat. Ensure that you biopsy the entire depth of the lesion, since depth in mm is the major prognostic feature of stage I and II melanoma.
Risks
Local hematoma, pain, or excessive bleeding at the site
Injury to nerves and other local structures
Infection at the site
Scarring
Sharps injury to healthcare personnel
Vasovagal response (fainting)
References
Ramsey ML, Rostami S. Skin Biopsy. [Updated 2021 Jun 4]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK470457/
Pickett H. Shave and punch biopsy for skin lesions. Am Fam Physician. 2011;84(9):995-1002.
Zuber TJ. Punch biopsy of the skin. Am Fam Physician. 2002;65(6):1155-1164.
Hellenberg D. How to do a skin biopsy, cryotherapy and electrotherapy. In: Mash B, Blitz-Lindeque J, eds. South African Family Practice Manual. 2nd ed. Pretoria: Van Schaik Publishers; 2010:160-161.