Excision biopsy involves the complete removal of a skin lesion by cutting it out. One common reason for excision is to eliminate skin cancer, such as basal cell carcinoma, squamous cell carcinoma, and melanoma.

Other reasons for removing a skin lesion include: obtaining a diagnosis, enhancing cosmetic appearance, alleviating symptoms (if the lesion is tender or prone to injury), and eliminating an inflamed or frequently infected cyst. 

It is important to note that some form of scarring is inevitable when fully excising a skin lesion. Skilled surgical techniques aim to minimize scarring by considering the tension lines of the skin surface.

Certain individuals may exhibit an abnormal response to skin healing, resulting in larger and thicker scars than usual (known as keloid or hypertrophic scarring). 

Your dermatologist will explain why excision is necessary for the skin lesion and describe the procedure involved. You may need to provide consent by signing a form indicating your understanding and agreement with the surgical procedure. Inform your doctor about any medications you are taking (especially aspirin, clopidogrel, dabigatran, and warfarin, as they can increase bleeding), allergies, medical conditions, or the presence of a pacemaker or implanted defibrillator. Additionally, disclose any over-the-counter supplements or herbal remedies, as some of these can also lead to abnormal bleeding.

The most common excision technique is elliptical excision. The ellipse is often designed to align the resulting scar with existing skin creases, reducing tension on the wound and making the scar less noticeable.

The area to be excised is marked with a surgical marker. A local anaesthetic injection is administered to numb the skin and maintain numbness during the procedure. The dermatologist then uses a scalpel and sharp scissors to cut around and under the lesion, along with an appropriate margin of healthy surrounding tissue. The excised lesion is placed in formalin for transfer to the pathology laboratory, where a pathologist will process and examine the specimen under a microscope and provide a report to your doctor a few days later.

During the surgery, there may be some bleeding from the excision site. The doctor may use cautery to coagulate the blood vessels. This can produce a hissing sound and a burning smell but is not felt by the patient.

Next, the edges of the ellipse are sewn together using sutures to create a thin suture line. This closure method is known as primary closure. It may involve two layers of sutures: an absorbable layer underneath and surface sutures that need to be removed in 4-14 days. In some cases, special skin glue may be used instead of sutures to join the edges together.

After the procedure, a wound dressing may be applied, and you will receive instructions on wound care and when to remove the stitches. The wound may become tender once the local anaesthetic wears off, typically 1-2 hours after the excision. 

It is recommended to leave the dressing in place for 48 hours or as advised by your dermatologist. Avoid strenuous activity and stretching the area until the stitches are removed and for some time afterwards.

If there is any bleeding, apply firm pressure on the wound with a clean folded towel without removing the existing dressing for 20 minutes. If bleeding persists after this time, seek medical attention.

Keep the wound dry for 48 hours. Afterwards, gently wash and dry the wound. A slight pinkness and tenderness around the wound edges are normal, but if the wound becomes increasingly red or painful, consult your dermatologist promptly, as it may indicate an infection requiring antibiotics.

Initially, the scar may appear red and raised, but it usually fades in color and decreases in size over several months.