Goals

To provide a full-thickness tissue specimen for diagnosis of questionable dermatologic lesions, including possible malignancies.

Background

A punch biopsy results in a full-thickness tissue specimen and can be used for lesions that require dermal or subcutaneous tissue for diagnosis. Examples of situations in which a punch biopsy may be used include inflammatory or bullous lesions, complex nevi that are too large to be excised, and scalp or hair follicle biopsies. The punch biopsy may also be an appropriate technique to remove small lesions. The biopsy is done using a skin punch instrument with a circular blade. The blade extends through to the subcutaneous fat and provides a cone-shaped specimen of tissue with the widest diameter at the skin surface and the narrowest at the biopsy base.  Punch biopsy instruments range in diameter from 2mm to 10mm, but 3mm is the smallest size that is likely to give a specimen large enough for accurate diagnostic assessment. This method is not an appropriate procedure for eyelids, lips, or penile lesions.

Contraindications

Referral to dermatology may be warranted in the following situations:

• History of keloids or hypertrophic scars
• Impaired hemostasis
• Diabetes with history of poor wound healing
• Immunosuppression
• Potential for malignant lesion