Excisional Biopsy of Skin Lesions

Excisional biopsy is the term used to describe the removal of skin lesions by completely cutting them out of the affected site. The procedure is usually performed under local anaesthetic, which is injected into the skin to numb the area. The injection may cause brief stinging. After the procedure is completed, a suture or dressing may be applied to the biopsy site.

There are different types of skin biopsies: punch biopsy, shave biopsy, curettage, incisional biopsy, and excision biopsy.

Punch Biopsy

A punch biopsy is considered to be the most useful type of biopsy. It is quick to perform, convenient, and leaves a small wound. The skin sample is of full thickness, which enables the pathologist to review the epidermis, dermis, and subcutis.

A disposable skin biopsy punch is used, fitted with a round stainless steel blade ranging from 2 to 6 mm in diameter. The most common sizes are 3 mm and 4 mm. The instrument is held perpendicular to the skin and rotated to pierce through it. The skin sample is then removed with the assistance of forceps and scissors.

Shave Biopsy

Shave biopsy is used for superficial skin lesions, such as to confirm a diagnosis of basal cell carcinoma. A tangential shave of the skin is performed using a scalpel, a specialised shave-biopsy instrument, or a razor blade. Stitches are not required. The wound typically heals within one to three weeks.

Curettage

A skin curette is used for scraping off superficial skin lesions, such as seborrhoeic keratosis. It is important to note that samples obtained by curettage are not used to determine whether a lesion has been completely removed.

Incisional Biopsy

Incisional biopsy is used to remove larger and deeper portions of skin using a scalpel blade. Stitches are required to close the wound.

Excision Biopsy

Excision biopsy is used for the complete removal of skin lesions, such as skin cancer. A margin of surrounding skin is included to improve the likelihood of complete cancer removal. Smaller lesions are removed with a scalpel blade, while larger lesions may require a skin flap, in which adjacent skin is moved to cover the wound site, or a graft, in which skin is taken from another site to patch the wound.

Possible Complications

Skin biopsy is generally a straightforward procedure, and post-procedure complications are uncommon. However, the larger the area of skin removed, the greater the risk of possible complications.

Intraoperative and postoperative bleeding may occur in any patient. Bacterial wound infection occurs in approximately 1 to 5 percent of excision biopsies and is uncommon following small punch, shave, or incisional biopsies. The biopsy site, the presence of ulcerated or crusted skin lesions, older age, diabetes, or the use of immunosuppressive medications may increase the risk of wound infection.

Permanent scarring following biopsy is relatively common. Certain body sites, such as the centre of the chest, are prone to the development of excessive or hypertrophic scars.