Excisional Surgery
Excisional surgery and reconstruction is close to the gold-standard treatment in dermatology for malignant skin tumors (basal cell carcinoma, BCC; squamous cell carcinoma, SCC; melanoma), precancerous lesions and large benign growths on the face and body. It has two parallel goals: to remove the diseased tissue completely with a histologically adequate margin of healthy tissue (surgical margins), and to restore the anatomy and appearance of the resulting defect as well as possible using layered closure, skin flaps or skin grafts.
At Haute-Derma, every excision and reconstruction is planned around the relaxed skin tension lines (RSTLs), the mobility of the surrounding tissue and the histologic margin check, to achieve the highest possible cure rate and a flat, fine scar.
Safe Surgical Margins
Setting Safe Surgical Margins
The margin is measured from the visible or palpable edge of the lesion out to the incision line in the surrounding healthy skin:
- Basal Cell Carcinoma (BCC):
- Low risk (superficial or nodular BCC on the trunk/limbs): 4 mm margin (clear margins in more than 95% of cases).
- High risk (morpheaform/infiltrative BCC, facial H-zone): 6–10 mm margin, or referral for Mohs micrographic surgery.
- Squamous Cell Carcinoma (SCC):
- Low-risk SCC (< 2 cm, well differentiated): 4–6 mm margin.
- High-risk SCC (> 2 cm, poorly differentiated, deeply invasive): 6–10 mm margin.
- Melanoma (in situ and invasive):
- Melanoma in situ: 5 mm margin.
- Invasive melanoma (Breslow < 1.0 mm): 1 cm margin.
- Invasive melanoma (Breslow 1.01–2.0 mm): 1–2 cm margin.
Designing the Elliptical Excision
A standard ellipse has a length-to-width ratio of 3:1 to 4:1 with 30-degree apical angles, and its long axis must run exactly parallel to the relaxed skin tension lines (RSTLs). These proportions prevent a “dog-ear” deformity—a pucker of excess tissue at either end of the ellipse when the edges are brought together.
Reconstruction Techniques
- Primary Layered Closure:
- How it works: The surgeon undermines the superficial subcutaneous fat around the defect with scissors to release tension.
- Deep dermal sutures: Buried absorbable sutures (PDS or Vicryl 4-0/5-0) are placed in the deep dermis. This layer carries most of the tension, so the epidermal edges meet naturally without being starved of blood.
- Local Skin Flaps:
- Key feature: A section of skin and subcutaneous tissue with its own blood supply (pedicle) is moved from nearby to cover the defect. This gives an excellent match in color, thickness and texture.
- Main flap types:
- Advancement flap: Single or double flaps (U-plasty, H-plasty) slide in a straight line into the defect.
- Rotation flap: A curved flap pivots around a fixed point to cover a triangular defect.
- Transposition flap (rhomboid/Limberg, bilobed): The flap is lifted over adjacent healthy skin into the defect; it works especially well on the nasal ala and the ear.
- Skin Grafts:
- Key feature: The graft is completely detached from the donor site, losing its blood supply. For the first 48 hours it survives by absorbing plasma from the wound bed (plasma imbibition) before new capillary connections form (inosculation).
- Types:
- Full-thickness skin graft (FTSG): Includes the entire epidermis and dermis. It shrinks little and looks very natural (usually taken from behind the ear or above the collarbone).
- Split-thickness skin graft (STSG): Includes the epidermis and part of the dermis. It takes more reliably but tends to contract and darken.
Comparing Reconstruction Techniques After Skin Surgery
| Technique | Best Suited For | Cosmetic Advantages |
|---|---|---|
| Primary layered closure | Small to medium defects with mobile surrounding skin | A single fine scar that matches the skin color exactly |
| Local flap | Facial defects (nose, cheek, eyelid, lip) | Very close match in color, texture and thickness |
| Full-thickness skin graft (FTSG) | Large facial or ear defects where a flap is not possible | Preserves skin thickness with little distortion of nearby structures |
| Split-thickness skin graft (STSG) | Large or deep defects on the trunk and limbs | Covers large areas easily, with a high graft survival rate |
Surgical Safety, Managing Complications and Graft Care
- Dog-Ear Deformity:
- Cause: Occurs when the two sides of the ellipse are unequal in length or the apical angle is too wide (> 30 degrees).
- Correction: A small compensating triangle (Burow’s triangle) is excised at the base of the pucker to remove the excess tissue, and the edges are sutured flat.
- Hematoma Under a Flap or Graft: Hematoma is the leading cause of graft failure. FTSGs should be lightly fenestrated (small drainage slits) and held down with a tie-over bolster dressing left in place for 5–7 days.
- Trapdoor (Pincushion) Deformity: The flap bulges up like a dome above the surrounding skin because a circular scar contracts beneath it. It is prevented by wide undermining of the defect bed and careful buried dermal sutures.
Our Excision and Reconstruction Process at Haute-Derma
Marking Margins and Designing the Flap or Incision
- Surgical loupes or dermoscopy are used to define the edges of the lesion.
- The ellipse or reconstruction flap is drawn along the RSTLs with a standard safety margin (4–10 mm depending on the diagnosis).
- Local anesthetic is injected: lidocaine 1% with epinephrine 1:100,000.
Removing the Lesion and Controlling Bleeding
- The skin is incised at 90 degrees down to the superficial subcutaneous fat or to the periosteum (depending on tumor depth).
- The whole specimen is removed, marked for orientation (a suture at 12 o’clock) and sent for histopathology (permanent or frozen sections).
- Bleeding in the wound bed is carefully controlled with bipolar electrocautery.
Reconstruction and Wound Closure
- The wound edges are undermined to release tension.
- Layered closure: buried deep dermal sutures with Vicryl 4-0/5-0, then epidermal closure with Prolene/nylon 6-0.
- For an FTSG, a tie-over dressing holds the graft in place for 7 days.
