Lip Reconstruction After Mohs Micrographic Surgery: A Guide on Flaps
The lips are commonly affected by skin cancer because of increased sun exposure over time. Even with early detection, many of these skin cancers require surgical removal with subsequent reconstruction. Mohs micrographic surgery is the preferred method of treatment for nonmelanoma skin cancers of the lip, as it has the lowest recurrence rates and allows for the maximum preservation of healthy tissue. After surgery, the remaining lip defect often requires reconstruction with skin grafts or a local cutaneous or myocutaneous flap. There are several local flap reconstruction options available, and some may be used in combination for more complex defects. We provide a succinct review of commonly utilized flaps and outline their indications, risks, and benefits.
Practice Points
- Even with early detection, many skin cancers on the lips require surgical removal with subsequent reconstruction.
- There are several local flap reconstruction options available, and some may be used in combination for more complex defects.
- The most suitable technique should be chosen based on tumor location, tumor stage or depth of invasion (partial or full thickness), and preservation of function and aesthetics.
Upper lip full-thickness defects that are too big for an Abbé-Estlander flap are closed with the Gillies fan flap.18 These defects involve 70% to 80% of the horizontal lip.9 The Gillies fan flap design redistributes the remaining lip to provide similar tissue quality and texture to fill the large defects.9,23 Compared to Karapandzic and Bernard flaps, Gillies fan incision closures are hidden well in the nasolabial folds, and the degree of microstomy is decreased because of the rotation of the flaps. However, rotation of medial cheek flaps can distort the orbicular muscular fibers and the anatomy of the commissure, which may require repair with commissurotomy. Drawbacks include a risk for denervation that can result in temporary oral sphincter incompetence.23 The bilateral Gillies fan flap carries a risk for microstomy as well as misalignment of the lip vermilion and round commissures.21
The Karapandzic flap is similar to the Gillies fan flap but only involves the skin and mucosa.9 This flap can be used for lateral or medial upper lip defects greater than one-third the width of the entire lip. This single-procedure flap allows for labial continuity, preserved sensation, and motor function; however, microstomia and misalignment of the oral commissure are common.1,18,21 In a retrospective study by Nicholas et al,4 the only flap reported to have a poor functional outcome was the Karapandzic flap, with 3 patients reporting altered sensation and 1 patient reporting persistent stiffness while smiling.
The BW flap can be applied for extensive full-thickness defects greater than one-third the lower lip and for defects with limited residual lip. This flap also can be used in cases where only skin is excised, as the flap does not depend on reminiscent lip tissue for reconstruction of the new lower lip. Sensory function is maintained given adequate visualization and preservation of the local vascular, nervous, and muscular systems. Disadvantages of the BW flap include an incision notch in the region of the lower lip; blunting of the alveolobuccal sulcus; and functional deficits, such as lip incontinence to liquids during the postoperative period.21
The Bernard-Burrow-Webster flap is used for large lower lip defects and preserves the oral commissures by advancing adjacent cheek tissue and remaining lip tissue medially.10 It allows for larger site mobilization, but it is possible to see some resulting oral incontinence.1,10 The Burow wedge flap is a variant of the advancement flap, with the Burow triangle located lateral to the oral commissure. Caution must be taken to avoid intraoperative bleeding from the labial and angular arteries. In addition, there also may be downward displacement of the vermilion border.5
How to Choose a Flap
The orbicularis oris is a circular muscle that surrounds both the upper and lower lips. It is pulled into an oval, allowing for sphincter function by radially oriented muscles, all of which are innervated by the facial nerve. Other key anatomical structures of the lips include the tubercle (vermilion prominence), Cupid’s bow and philtrum, nasolabial folds, white roll, hair-bearing area, and vermilion border. The lips are divided into cutaneous, mucosal, and vermilion parts, with the vermilion area divided into dry/external and wet/internal areas. Sensation to the upper lip is provided by the maxillary division of the trigeminal nerve via the infraorbital nerve. The lower lip is innervated by the mandibular division of the trigeminal nerve via the inferior alveolar nerve. The labial artery, a branch of the facial artery, is responsible for blood supply to the lips.3,9 Because of the complex anatomy of the lips, careful reconstruction is crucial for functional and aesthetic preservation.
There are a variety of lip defect repairs, but all local flaps aim to preserve aesthetics and function. The Table summarizes the key risks and benefits of each flap. Local flap techniques can be used in combination for more complex defects.3 For example, Nadiminti et al19 described the combination of the Abbé flap and V-Y advancement flap to restore function and create a new symmetric nasolabial fold. Dermatologic surgeons will determine the most suitable technique based on tumor location, tumor stage or depth of invasion (partial or full thickness), and preservation of function and aesthetics.1
Other factors to consider when choosing a local flap are the patient’s age, tissue laxity, dentition/need for dentures, and any prior treatments.7 Scar revision surgery may be needed after reconstruction, especially with longer vertical scars in areas without other rhytides. In addition, paresthesia is common after Mohs micrographic surgery of the face; however, new neural networks are created postoperatively, and most paresthesia resolves within 1 year of the repair.4 Dermabrasion and Z-plasty also may be considered, as they have been shown to be successful in improving final outcomes.9 Overall, local flaps have risks for infection, flap necrosis, and bleeding, though the incidence is low in reconstructions of the face.
Final Thoughts
There are several mechanisms to repair upper and lower lip defects resulting from surgical removal of cutaneous cancers. This review of specific flaps used in lip reconstruction provides a comprehensive overview of indications, advantages, and disadvantages of available lip flaps.
