Equipment needed for excisional biopsy includes alcohol swab, marking pen, lidocaine and syringe, gauze, sterile towel, scalpel, pick up, tissue scissors, specimen bottle, tissue hook, needle driver, suture, Vaseline, dressing. Biohazard bag and pathology request. Indications for excisional biopsy, large vessel vasculitis, most pigmented lesions, deep or subcutaneous nodules, malignant neoplasms, suspected metastases, lesions larger than 6 millimeters, when the presumed pathology involves deep dermis or subcutis. The area to be biopsied is draped, cleansed and prepped with an alcohol swab. Align the long axis of the excision parallel to skin tension lines. Using a surgical marking pen, draw an ellipse around the lesion to be excised, including a 2 to 5 millimeter margin of normal skin around the lesion with 30 degree angles at each apex and the length 3 to 4 times the width. Recommended margins, 1 to 2 millimeters for benign lesions, 4 to 5 millimeters for nodular basal cell carcinomas, 5 to 6 millimeters for squamous cell carcinomas. Margins vary for melanomas. The lesion is injected with 1% lidocaine with epinephrine buffered with sodium bicarbonate using subcutaneous injections followed by intradermal injections. Anesthesia is confirmed by probing the area with the tip of the needle. Begin the incision at one apex with the blade perpendicular to the skin. Hold the number 15 blade like a pencil in the dominant hand while the other hand applies gentle tension to immobilize the skin around the ellipse. Counter traction by an assistant is also helpful. Number 15 blades are generally used for the face and neck lesions. Number 10 blades are used for thick skin on the trunk, scalp and extremities. As the incision progresses, use more of the belly of the blade. You can achieve this by lowering the blade to a 45 to 60 degree angle. When approaching the proximal apex, the blade is once again raised to a vertical position. The incision must extend completely through the dermis and be deep enough to see subcutaneous fat when the sample is removed. Care should be taken to handle the tissue delicately to prevent damage to the epidermis. Cut with enough pressure to reach subcutaneous tissue in 1 to 2 strokes to avoid stair casing of the dermis and avoid cross hatching of the tips of the ellipse. Carefully lift the sample edge with fine forceps once the ellipse has been incised and completely undermine the sample at the level of the subcutaneous fat with scalpel or scissors. Do not remove more tissue at the center than at the apices. Leaving a larger amount of tissue at the tips creates an unsightly elevation or boating effect at closure. Apply pressure to the wound with gauze and the use of a hyphrocator for hemostasis in preparation for closing. Suturing is required for excisional biopsies. As illustrated by the video, the wound edge closest to the surgeon is gently grasped with the pickups. The needle is inserted through the dermis in a low to high fashion. The opposite side of the wound is gently grasped next and the needle is placed through the dermis in a high to low fashion. The vicral suture is then tied using instrument tie with a double throw at the beginning. More vicral sutures are placed across the length of the entire wound. Non-absorbable sutures are used for epidermal suturing. In this instance, nylon was chosen. The epidermal sutures are used for approximating the wound edges. A dressing is applied to the wound. First, the use of Vaseline or antibiotic ointment, followed by a non-adherent dressing, then the use of gauze. All of this is wrapped with a compression bandage. Some comments regarding excisional biopsies. They require the greatest amount of expertise and time, pose more risk and discomfort for patients, and must be closed with sutures. They are more easily performed with an assistant. It is the preferred biopsy technique for pigmented lesions greater than 4 mm. When less than 4 mm, a punch biopsy can be used. Their main advantage is the amount of tissue that can be removed, allowing for multiple studies from one biopsy site. Alternatively, an incisional biopsy may be used. Similar indications and technique as excisional biopsy. In this type of biopsy, however, only a portion of a large lesion is removed. The specimen should include the thickest and most representative area of the lesion and extend through the edge of the plaque or tumor into the adjacent normal skin. When applied to pigmented lesions, the darkest and most nodular appearing area of the lesion should be sampled. The incision must be deep enough to sample an adequate amount of fatty tissue, but may be only a few mm wide. Biopsied sites are usually closed with absorbable sutures. The pathology requisition should include a special request for the embedding and specimen for sectioning in the long axis of the specimen.

excisional biopsy

equipment

steps

indications

anesthesia