If your dermatologist has recommended Mohs micrographic surgery for a skin cancer, you have been offered the most precise cancer-removal technique available. What often surprises patients is what comes next: the careful, creative work of rebuilding the area of skin that has been removed. That is where the plastic surgeon steps in.
This guide explains what Mohs is, why reconstruction is so often needed, and what the different surgical options involve. My aim is that you arrive at your reconstructive consultation knowing the vocabulary and feeling prepared to take part in the decision.
What is Mohs surgery?
Mohs micrographic surgery is a specialised technique performed by a trained dermatological surgeon, usually under local anaesthetic. The visible tumour is removed in thin horizontal layers, and each layer is processed and examined under a microscope in real time. If any residual cancer is found at the edges, only that specific area is returned to and removed. The process continues — typically across two or three layers — until the margins are clear.
The result is the highest cure rate of any skin cancer treatment (exceeding 97% for primary basal cell carcinoma) while sacrificing the smallest possible amount of healthy tissue. The trade-off is that Mohs inherently produces an open, irregular defect that needs to be reconstructed, often on the same day.
Why reconstruction is needed
Even though Mohs is tissue-sparing, the defects it leaves can be surprisingly deep or wide — particularly on the face, where tumours have a habit of extending beneath apparently innocuous surface changes. Left to heal on their own, many defects would eventually close but might leave a depressed, tethered or distorted scar. Reconstruction aims to do three things at once:
- Restore function — so the eyelid still closes, the nostril still breathes, the lip still moves.
- Restore form — replacing missing skin, and sometimes cartilage or soft tissue, to match the original contour.
- Minimise scarring — by placing incisions in natural creases, matching skin tone and texture, and rebuilding with like-for-like tissue.
Who performs Mohs reconstruction?
Reconstruction after Mohs is usually undertaken by a plastic surgeon with a particular interest in skin cancer and facial reconstruction. Many dermatological surgeons also perform their own repairs for smaller defects. For more complex cases — especially those on the nose, eyelid, ear or lip — a formal reconstructive consultation with a plastic surgeon is the standard of care.
The main reconstructive options
Primary closure
The simplest option. If the defect is small enough, the edges can be mobilised and brought together directly, usually along the line of a natural skin crease. The resulting scar is a fine line and tends to fade beautifully. Primary closure is ideal where skin is generous, such as the cheek, forehead or upper chest.
Skin grafts
A skin graft involves borrowing skin from elsewhere and transplanting it to cover the defect. There are two principal types:
- Full-thickness skin graft: the entire thickness of skin is harvested from a donor site (often in front of or behind the ear, or the supraclavicular area). The colour and texture match tend to be excellent, which is why these grafts are our preference on the face.
- Split-thickness skin graft: only the top layer of skin is harvested, usually from the thigh. These grafts take on very well and cover larger areas but may look paler and shinier than the surrounding skin.
Grafts require a clean, well-vascularised wound bed and a dressing that holds the graft firmly in place for the first five to seven days.
Local flaps
A local flap uses adjacent skin — still attached to its own blood supply — to fill the defect. Because the flap brings its own like-for-like skin with matching colour, texture and thickness, the cosmetic result is often superb. Common flap designs include:
- Rotation flaps: a curved piece of skin rotated into the defect.
- Advancement flaps: skin pushed forward in a straight line.
- Transposition flaps (such as bilobed or rhomboid flaps): skin swung around a pivot point, often used elegantly on the nose.
Local flaps are planned so the resulting scars lie in natural lines. A well-designed flap on the cheek or forehead can be almost invisible six months down the line.
More complex flaps
For larger or more challenging defects — classically on the nose or around the eye — we sometimes use regional flaps that bring tissue from a nearby area. The paramedian forehead flap, for example, uses a paddle of forehead skin to rebuild a nose, and is one of the most reliable and beautiful options for complex nasal reconstruction. These flaps are typically performed in two stages around three weeks apart.
Free flaps
Very occasionally, a free flap is needed — a piece of tissue transplanted with its own blood vessels, reconnected under the microscope to vessels at the recipient site. This is uncommon for routine Mohs reconstruction and is reserved for large or complicated defects.
"Good reconstruction is half science and half artistry. The best results come from thinking in three dimensions, respecting the natural subunits of the face, and accepting that sometimes a staged approach gives a far better end result than rushing to close."
Staged reconstruction
Occasionally we deliberately delay reconstruction by a few days. This might be done if the final histology is awaited, if the wound needs to settle, or if a two-stage flap is planned. In the meantime, a simple dressing or temporary closure protects the area and patients are more comfortable than they expect.
Cosmetic considerations on the face
The face is divided into cosmetic subunits — the nose, eyelid, lip, cheek, forehead — each with its own unique skin, contour and importance. The core principle of facial reconstruction is to respect these boundaries. It is almost always better to rebuild an entire subunit with one piece of matched tissue than to leave a patchwork of small grafts within it. That is particularly true of the nose, where small differences in skin thickness or sebaceous quality show immediately.
The eyelid requires specialist attention to preserve the ability to close, blink and protect the cornea. The lip demands accurate alignment of the vermilion border and careful muscle repair. The ear calls for cartilage support and respect for its delicate folds.
Recovery and scar expectations
Most reconstructions are performed under local anaesthetic as a day-case, sometimes with sedation. In the days and weeks that follow you can expect:
- First week: swelling, bruising, a simple dressing, and minor discomfort controlled with paracetamol. Sutures are typically removed between five and seven days on the face.
- Two to six weeks: the scar may look pink, firm or slightly raised — this is the remodelling phase and is entirely normal.
- Three to six months: softening and fading. Scar massage with a silicone product and strict sun protection make a measurable difference.
- Twelve months: final appearance. Most scars become pale, flat and subtle — often far better than patients imagine at the point of the Mohs defect.
What to expect at the reconstructive consultation
If Mohs has been recommended, I typically see patients in clinic either before surgery (to plan in advance) or immediately afterwards on the same day. We discuss the size and position of the expected defect, the reconstructive options, likely scar trajectory, and any functional concerns. Photographs are always taken for the medical record, and I encourage patients to ask about anything — from showering and exercise to when they can return to work or social events.
For further reading, our article on early signs of skin cancer may be useful if you are at the start of this pathway, and you can find an overview of our skin cancer service on the Skin Cancer Centre page. Information on scar care is available in our scar management guide.
